(NEW YORK) — Saturday marks 20 years since the 9/11 terrorist attacks.

Hijackers crashed two commercial airliners into the World Trade Center, striking the north tower at 8:46 a.m. followed by the south tower at 9:03 a.m. At 9:37 a.m., a third hijacked airline crashed into the Pentagon.

Twenty-two minutes later, the World Trade Center’s south tower collapsed. A fourth hijacked plane crashed into a field in rural Shanksville, Pennsylvania, at 10:03 a.m. after passengers fought with and overcame the hijackers.

At 10:28 a.m. the World trade Center’s North Tower collapsed.

In total, 2,977 people were killed, including many New York City first responders.

The anniversary will be marked by several events across the country, including the annual commemoration at the World Trade Center Memorial in downtown Manhattan.

Here’s how the news was developing. All times Eastern.

Sep 11, 10:40 am
NATO marks 20th anniversary with memorial ceremony

NATO marked the 20th anniversary of the Sept. 11 attacks on Saturday with a commemoration ceremony in Brussels.

Secretary General Jens Stoltenberg was joined by the U.S. Mission to NATO’s Chargé d’Affaires Douglas D. Jones at the ceremony.

A wreath was laid and those in attendance fell silent as they paid their respects to those who died in the attacks

-ABC News’ Guy Davies

Sep 11, 10:35 am
6th, final moment of silence held

A sixth moment of silence was held at the World Trade Center memorial at 10:28 a.m. to mark the time when the North Tower collapsed.

It was the final moment of silence of the day’s ceremonies.

After bells tolled, “Hamilton” actor Chris Jackson performed “Never Alone.”

Sep 11, 10:08 am
5th moment of silence observed

A fifth moment of silence took place at 10:03 a.m., the time when Flight 93 crashed in Shanksville, Pennsylvania, after passengers fought with and overcame the hijackers.

Bells tolled at the memorial site near where the plane crashed as well as at the World Trade Center memorial.

Sep 11, 10:03 am
4th moment of silence observed

A fourth moment of silence took place at 9:59 a.m., the time when the south tower of the World Trade Center collapsed.

Bells tolls at the at the National September 11th Memorial & Museum and at locations across the city to mark this moment.

Sep 11, 9:56 am
Defense Secretary Lloyd Austin honors lives lost at Pentagon

Defense Secretary Lloyd Austin spoke at the Sept. 11 memorial at the Pentagon, honoring the 184 people killed in the building and aboard Flight 77.

“Today, we remember not just who our fallen teammates were, but the mission that they shared. And we recall their common commitment to defend our republic, and to squarely face new dangers,” he said.

Austin talked about the members of the military who were born after the attacks and the sacrifices they’ve made to keep the nation safe, including the 13 service members who were killed in Afghanistan last month.

“It is our responsibility to remember, and it is our duty to defend our democracy,” he said.

-ABC News’ Matt Seyler

Sep 11, 9:47 am
3rd moment of silence held

At 9:37 a.m. a third moment of silence was held to mark the time when Flight 77 struck the Pentagon.

“Taps” played outside the Pentagon, while at the World Trade Center, a bell tolled.

Sep 11, 9:36 am
World leaders send their condolences on 20th anniversary

Leaders from around the world shared their reflections and condolences on the 20th anniversary of the Sept. 11 attacks.

Queen Elizabeth said in a statement she was still moved by the unity shown by the world during such a tragic time.

“It reminds me that as we honour those from many nations, faiths and backgrounds who lost their lives, we also pay tribute to the resilience and determination of the communities who joined together to rebuild,” she said in a statement.

The U.S. national anthem played at the changing of the guard at Windsor Castle.

Ursula von der Leyen, the president of the European Union Commission, tweeted, “The EU stands with the USA in defending freedom & compassion over hate.”

UN Secretary General Antonio Guterres issued a statement honoring first responders and that his “thoughts are with the victims and their families.”

-ABC News’ Guy Davies

Sep 11, 9:29 am
Bruce Springsteen performs solemn tribute

Bruce Springsteen performed following the second moment of silence at the World Trade Center memorial service.

His song “I’ll See you in My Dreams,” was dedicated to all of the lives lost that day.

Sep 11, 9:12 am
2nd moment of silence held

A second moment of silence was held at 9:03 a.m. to mark the time the south tower was hit.

A bell tolled at the World Trade Center memorial as well as other locations across the country.

Sep 11, 9:04 am
Families begin reading of names lost at World Trade Center

The families of the World Trade Center victims began their readings of the lives lost on Sept. 11.

Mike Low, whose daughter Sara was a flight attendant on Flight 11, spoke before the readings began. While he said his family’s pain is still raw, they have found comfort in the community and outpouring of support from all over the world.

“As we recite the names we lost my memory goes back to that terrible day when it felt like an evil specter descended on our world, but it was also a time when people went above and beyond the ordinary,” Low said.

Sep 11, 8:51 am
1st moment of silence held at World Trade Center

The memorial services at the National September 11th Memorial & Museum began with a color guard, bagpipes and a singing of the National Anthem.

The first moment of silence took place at 8:46 a.m., the time when the first plane struck the north tower.

A bell tolled to mark the moment and was echoed by bells across the city.

Sep 11, 9:15 am
Former presidents join Biden at World Trade Center

Former Presidents Barack Obama and Bill Clinton, former Secretary of State Hillary Clinton and former first lady Michelle Obama joined President Biden and first lady Jill Biden at the National September 11th Memorial & Museum ceremonies.

Former President George W. Bush is scheduled to meet with families in Shanksville, Pennsylvania.

Sep 11, 8:36 am
Crowds begin to gather at World Trade Center

Families of World Trade Center victims, survivors, first responders and dignitaries have begun gathering at the National September 11th Memorial & Museum for this year’s memorial services.

The event begins at 8:30 a.m. and is expected to conclude at approximately 1:00 p.m.

The ceremony will include moments of silence at the times the four planes crashed and the times both towers collapsed.

Family members will read the names throughout the morning of all of the people lost that day as well as the victims of the 1993 World Trade Center bombing.

Sep 11, 8:01 am
Obama reflects on 20th anniversary

Former President Barack Obama released a statement Saturday morning reflecting on the 20th anniversary of the Sept. 11 attacks.

He urged all Americans to remember the courage and selflessness of those lost in the attacks.

“We reaffirm our commitment to keep a sacred trust with their families — including the children who lost parents, and who have demonstrated such extraordinary resilience. But this anniversary is also about reflecting on what we’ve learned in the 20 years since that awful morning,” Obama wrote.

“That list of lessons is long and growing. But one thing that became clear on 9/11 – and has been clear ever since – is that America has always been home to heroes who run towards danger in order to do what is right.”

In his statement the former president pointed to examples of heroic actions from the last two decades, such as the service members, first responders and medical personnel.

“They represent what is best in America, and what can and should bring us together,” Obama said. “9/11 reminded us how so many Americans give of themselves in extraordinary ways – not just in moments of great crisis, but every single day. Let’s never forget that, and let’s never take them for granted.”

-ABC News’ Molly Nagle

Sep 11, 8:20 am
President Biden to attend services at World Trade Center, Shanksville, Pentagon

President Joe Biden and first lady Jill Biden will attend three 9-11 memorial services throughout the day

They will begin at the National September 11th Memorial & Museum in lower Manhattan at 8:30 a.m. and fly out to Shanksville, Pennsylvania. The president and first lady will attend a wreath-laying ceremony at the Flight 93 National Memorial at 12:30 p.m.

They will be joined by Vice President Kamala Harris and the second gentleman Doug Emhoff at the Pentagon at 4:30 p.m. where they will take part in the wreath-laying ceremony to honor the lives lost at the location.

Biden released a video speech on social media Friday evening marking the 20th anniversary.

“As we saw in the days that followed, unity is our greatest strength. It’s what makes us who we are — and we can’t forget that,” he tweeted.

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(WASHINGTON) — In the aftermath of President Joe Biden’s latest announcement that companies with over 100 employees must mandate vaccines or test all employees once a week, legal experts say the Department of Labor rule will be litigious and messy, but it just might work.

“There’s never been anything so extensive in American history that it requires vaccines across such a wide swath of Americans,” said Lawrence Gostin, a law professor at Georgetown University and director of the O’Neill Institute for National and Global Health Law.

“But I think he’s on rock-solid legal ground,” Gostin said.

Already, Republican governors have outlined plans to overturn the rule — which hasn’t even been implemented by the Occupational Safety and Health Administration — on behalf of their constituents who believe it infringes on their individual rights.

But experts who have reviewed the policy say Biden is acting within his power as president and backed by previous court decisions that have been pro-vaccine.

“I would argue that the basis for findings of grave danger and necessity, which is what statute requires, are probably stronger now for this use than they have been in OSHA’s 50-plus year history,” said Lindsay Wiley, a law professor at American University in Washington, D.C., and director of the school’s Health Law and Policy Program.

Generally, when the emergency statute has been used in the past, often for chemical exposure in the workplace, it’s also faced legal pushback. But it’s never been used in a public health emergency, Wiley noted.

“This is an unprecedented step, but unsurprisingly so given that it’s an unprecedented threat and situation,” she said.

David Michaels, the longest-serving administrator in OSHA history and a professor at the George Washington University School of Public Health, said the agency’s law is clear and straightforward: keep workers from getting infected at their jobs.

He was glad the Biden administration, which he advised during the transition, was finally utilizing it.

“The legal requirement is not to vaccinate someone or to say you have to be vaccinated — it’s, ‘This is what you must do to make sure the workplace is safe,'” Michaels said.

He called for the Biden administration to take the rule even further, extending it to all businesses rather than just those over 100 employees, and include an indoor mask mandate.

The next question is whether or not the federal government, confined to the tools available in a country that rests much of its power with the states, has enough teeth to enforce the mandates.

As an underfunded and understaffed agency, following up with two-thirds of America’s workforce to see if they’re either mandating vaccines or testing workers at least once a week would take OSHA 150 years, said Debbie Berkowitz, a former senior official at OSHA under President Barack Obama.

Wiley agreed, noting that the agency has historically been “pretty spotty” at upholding measures.

“I don’t know that OSHA has the resources to really go out and do a lot of inspections and really strongly enforce this provision,” Wiley said. But in states that are supportive of Biden’s rule, the state agencies could lend a hand, she said.

On the other hand, even with its checkered record, businesses generally comply with most other OSHA standards for fear of an investigation and a fine.

While OSHA is a small agency that “often can’t inspect every time a worker complains,” employers generally “know what they have to do” and will cooperate with the new rules when published, Berkowitz said.

And failing to comply with this particular rule could cost up to $14,000, the White House said Friday, which would be bad for business in more ways than one.

“There’s the embarrassment,” said Michaels. “If an employer is cited by OSHA, that’s public information, and a lot of employers don’t want to be seen as scofflaws.”

Gostin, the Georgetown professor, predicted that Biden would order OSHA to prioritize enforcement of the vaccine mandate above other regulations.

“At the very least OSHA will send a notice of the standard to every large business in America and give them a deadline,” he said.

The new mandates could also offer cover for businesses that wanted to enforce vaccine mandates or testing but didn’t feel empowered to make the call without backing from a powerful entity, White House coronavirus response coordinator Jeff Zients said at a briefing with reporters Friday.

“The president’s actions will accelerate that number of companies across the board for employers over a hundred,” Zients predicted.

But the administration acknowledged that they don’t have the legal authority to mandate vaccines nationwide.

“We don’t have the ability to tell every American, ‘You have to be vaccinated.’ There’s a means of encouraging it, of mandating it through certain pursuits or certain pathways, and that’s exactly what we’ve done,” White House press secretary Jen Psaki said Friday at a briefing.

Dr. Amesh Adalja, a senior scholar at the Johns Hopkins University Center for Health Security, said he thought companies would begin to implement mandates even before the rule takes effect because Biden’s announcement, even without the regulatory action officially in place, would be enough.

“The biggest short-term thing that’s going to happen is that many companies that were reticent to institute a vaccine mandate as a condition of employment are going to feel emboldened to do so now because they have the federal government kind of giving them a stamp of approval,” Adalja said.

ABC News’ Sasha Pezenik contributed to this report.

Copyright © 2021, ABC Audio. All rights reserved.

(NEW YORK) — Saturday marks 20 years since the 9/11 terrorist attacks.

Hijackers crashed two commercial airliners into the World Trade Center, striking the north tower at 8:46 a.m. followed by the south tower at 9:03 a.m. At 9:37 a.m., a third hijacked airline crashed into the Pentagon.

Twenty-two minutes later, the World Trade Center’s south tower collapsed. A fourth hijacked plane crashed into a field in rural Shanksville, Pennsylvania, at 10:03 a.m. after passengers fought with and overcame the hijackers.

At 10:28 a.m. the World trade Center’s North Tower collapsed.

In total, 2,977 people were killed, including many New York City first responders.

The anniversary will be marked by several events across the country, including the annual commemoration at the World Trade Center Memorial in downtown Manhattan.

Here are the latest updates from the day. All times are Eastern.

Here’s how the news was developing. All times Eastern.

Sep 11, 8:21 am
Crowds begin to gather at World Trade Center

Families of World Trade Center victims, survivors, first responders and dignitaries have begun gathering at the National September 11th Memorial & Museum for this year’s memorial services.

The event begins at 8:30 a.m. and is expected to conclude at approximately 1:00 p.m.

The ceremony will include moments of silence at the times the four planes crashed and the times both towers collapsed.

Family members will read the names throughout the morning of all of the people lost that day as well as the victims of the 1993 World Trade Center bombing.

Sep 11, 8:01 am
Obama reflects on 20th anniversary

Former President Barack Obama released a statement Saturday morning reflecting on the 20th anniversary of the Sept. 11 attacks.

He urged all Americans to remember the courage and selflessness of those lost in the attacks.

“We reaffirm our commitment to keep a sacred trust with their families — including the children who lost parents, and who have demonstrated such extraordinary resilience. But this anniversary is also about reflecting on what we’ve learned in the 20 years since that awful morning,” Obama wrote.

“That list of lessons is long and growing. But one thing that became clear on 9/11 – and has been clear ever since – is that America has always been home to heroes who run towards danger in order to do what is right.”

In his statement the former president pointed to examples of heroic actions from the last two decades, such as the service members, first responders and medical personnel.

“They represent what is best in America, and what can and should bring us together,” Obama said. “9/11 reminded us how so many Americans give of themselves in extraordinary ways – not just in moments of great crisis, but every single day. Let’s never forget that, and let’s never take them for granted.”

-ABC News’ Molly Nagle

Sep 11, 8:20 am
President Biden to attend services at World Trade Center, Shanksville, Pentagon

President Joe Biden and first lady Jill Biden will attend three 9-11 memorial services throughout the day

They will begin at the National September 11th Memorial & Museum in lower Manhattan at 8:30 a.m. and fly out to Shanksville, Pennsylvania. The president and first lady will attend a wreath-laying ceremony at the Flight 93 National Memorial at 12:30 p.m.

They will be joined by Vice President Kamala Harris and the second gentleman Doug Emhoff at the Pentagon at 4:30 p.m. where they will take part in the wreath-laying ceremony to honor the lives lost at the location.

Biden released a video speech on social media Friday evening marking the 20th anniversary.

“As we saw in the days that followed, unity is our greatest strength. It’s what makes us who we are — and we can’t forget that,” he tweeted.

Copyright © 2021, ABC Audio. All rights reserved.

(WASHINGTON) — What’s black and white and roaming the greater Washington, D.C., area?

Zebras.

“As if 2021 can’t get even more crazier, a pack of zebras were spotted in a Maryland county,” the National Park Service of Chesapeake Bay tweeted out earlier this week.

The group of five zebras, referred to as a dazzle, have been on the loose in Maryland for over a week now. The zebras escaped from a farm near Upper Marlboro, Maryland, late last month, Chief Rodney Taylor with Prince George’s County Animal Services Division told Washington ABC affiliate WJLA.

The farm has had exotic animals on and off for 15 years, Taylor told WJLA. Animal Services has received multiple calls that the quadrupeds were spotted roaming and grazing on the majestic plains of rural Maryland. The farm is working to lure the zebras back with feeding stations, where they hope they will be able to corral the zebras without spooking them.

The zebras are not dangerous unless you approach them, according to Taylor.

Congresswoman Eleanor Holmes Norton, D-Washington, D.C., inserted herself into the bizarre story by releasing a statement Friday denying responsibility for letting the zebras loose. Her office later clarified it was a joke. Holmes Norton said in jest that she had a “solid alibi” proving she did not release the zebras.

She is known locally as an advocate for consent of being governed — as she continues fighting for D.C. statehood — and joked in the statement that she opposes unnecessary fences.

“Local news has reported that the zebras were let loose on Saturday or Sunday of last weekend, a period of time during which I was enjoying quiet time at home with family,” Norton said. “My alibi is solid, but given my career of fighting for statehood for the District, which includes years of explaining the importance of having consent of the governed, and given my recent opposition to fences, I can understand why the charge was made. I hope the owners find the zebras and that all involved live long, full lives.”

The country requests that anyone with information about the whereabouts of the zebras contact Prince George’s County Animal Control Services at 301-780-7200.

Copyright © 2021, ABC Audio. All rights reserved.

(NEW YORK) — He was 39 years old, but those who knew Carl Asaro remember him as “a big kid.” He was a man who loved music, his wife, six children and his job as a firefighter.

“He would still have like a lot of energy and come play with all of the neighborhood kids,” his daughter Rebecca said. “He was big on riding his bike, throwing the football around and playing his guitar. If he wasn’t with us, that’s all he did. He was a huge Grateful Dead fan. He was either humming the songs or playing on the guitar.”

Asaro worked at Engine 54, only four miles from the World Trade Center.

On Sept. 11, 2001, he was one of the first responders who answered the call to help. Of the 15 people who left from Engine 54, Ladder 4 that day, none returned home.

Now, 20 years later, 65 children of New York firefighters who died have picked up their own helmets, inspired by their loved ones’ ultimate sacrifice.

“I think during this time it’s kind of expected to feel those old feelings and feel them resurge, but the days in between, when you don’t expect it — when a song comes on the radio and you see something that reminds you of him, those are the days that hit you a little bit harder,” Asaro’s son Carl Jr. said.

Four of the six Asaro children went on to continue his legacy as firefighters — Carl Jr., Matt, Rebecca and Mark, who were 13, 12, 9, and 7 on 9/11.

Rebecca remembers it was her mom’s turn to carpool that morning.

“I saw my dad that morning. That night before I asked him for tic tacs. I remember I was begging him, so before he went to work he dropped ‘em off and he kissed us goodbye,” she said.

“In school they kept calling us one by one. My mom when she picked me up… she was just so frantic… I remember my mom was back and forth on the phone,” she said. “I was 9 and didn’t really understand much of what was going on… I thought my dad pulled up one day and it was the chief to tell my mom what was going on. My mom didn’t understand so then it finally hit her days later that he wasn’t coming home.”

Matt took the bus home that day, knowing his dad was at ground zero.

“I was proud but I didn’t know what happened. I didn’t know the severity of it,” he said. “We didn’t have no cell phones back then, and I remember just calling him and beeping and no answer, no answer. That’s how life got to be without him. Coming down here and just waiting — people getting found everyday- alive, dead. They didn’t find nothing, not a bone, not a hair, not a memento. It just kind of sucked.”

Asaro’s body was never found, so his family opted to bury a guitar instead, filled with notes from loved ones — a symbol of his love of music.

Rebecca was eventually inspired to follow her dad’s footsteps as a firefighter by seeing his impact.

“It’s like the department’s small and my dad had such a big heart,” she said. “Through the years after 9/11 we talked to people.. He impacted so many.”

For Matt, he said the bond formed at the firehouse “is like no other.”

“We grew up here,” Carl Jr. said. “I think for us to give back and live a life of service is one way to really feel connected with my dad and for us to feel whole in a way.”

The siblings agreed that being a part of the FDNY helped them cope with the incredible loss.

“They’re a big part of our lives — has been and always will be,” Matt said, joking that his dad might have pointed out he wanted them to become doctors instead.

For five years, his namesake Carl Jr. didn’t visit ground zero. Now, he finds it peaceful, saying that because it was the last place his father was, he considers it his father’s final resting place.

On the eve of the anniversary of one of the darkest days in American history, Carl Jr. reflects on a discussion he had with his sister.

“We were talking about how you’re only truly dead when your name is mentioned for the last time, and I thought that was powerful,” he said. “If that’s the case my father and these men that were killed that day and sacrificed their life, they’re going to live forever through their legacy and their actions.”

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