"IT'S A DAY THAT WILL NEVER LEAVE YOU," FDNY COMMISSIONER DAN NIGRO TELLS SCOTT PELLEY ON THE 54th SEASON PREMIERE OF "60 MINUTES"

Marking the 20th Anniversary of 9/11, "60 Minutes" Will Broadcast "FDNY: 9/11," a Full Hour that Recalls the Heroism of New York Firefighters at Ground Zero

While the nation remembers the terrorist attacks that killed thousands of Americans 20 years ago, New York City firefighters sent to rescue victims at the World Trade Center who survived will relive a life-changing experience that's now a part of who they are. "It's a day that will never leave you," Fire Department of New York Commissioner Dan Nigro tells Scott Pelley. Nigro and other firefighters who were at Ground Zero, many of whom fill the top ranks of the FDNY, recall the men, their sacrifices and the tragedy of losing 343 of their colleagues in "FDNY: 9/11," to be broadcast on the 54th season premiere of 60 MINUTES, Sunday, Sept. 12 (7:30-8:30 PM, ET/7:00-8:00 PM, PT) on the CBS Television Network.

"A lot of bravery was displayed that day... followed by a lot of sadness," says Nigro. "I think for everyone that was there that day, it just stays with them, the sadness. We have plenty of good days, plenty to be thankful for, those of us who survived, but it's a day that'll never leave, never leave you."

The hour weaves together stories of heroism with archival footage, to reconstruct poignantly and accurately the tragic and valiant moment in American history when two of the four hijacked airliners in the terrorist attack hit the World Trade Center towers. The firefighters describe the bravery and the resignation of duty: no one refused orders to enter the buildings, and many who were trying to save victims refused the order to evacuate themselves. "They knew they might not come home," says retired Fire Department of New York Commissioner Sal Cassano.

Lieutenant Kevin Pfeifer didn't come home that day. His brother, retired Battalion Chief Joseph Pfeifer, recalls the cruel reality of duty.

"I could remember one lieutenant from Engine 33 coming up to me and not saying a word. And we stood there wondering if we were both going to be okay. And that lieutenant was my brother Kevin," he tells Pelley. "And then I told him what I told many of the other fire officers. I said, 'Go up to the 70th floor.'"

FDNY Chief of Department Peter Ganci was one of the 343 brave men who lost their lives on 9/11. 60 MINUTES also spoke to the firefighters who joined the FDNY after they lost fathers at Ground Zero. Ganci has two sons: Peter, a captain, and Chris, a battalion chief. Christ recalls: "I just remember them telling my mom that he's gone. And she said, 'Gone where?' Like that. Like, innocently. And they're like, 'He's dead.' And I remember the scream that she - that she let out. I can still hear it my ears, and it pains me to hear it." Peter says: "He loved being around family. But his family was also the fire department. We knew it. My mom knew it."

Nigro was Ganci's #2 as chief of operations on 9/11. They drove to Ground Zero together when the alarm was sounded. "So we went downstairs quickly, got in the car and headed over the Brooklyn Bridge, where we could see the damage, see the smoke, see the fire," he remembers. "That's when I said to Pete, 'Pete, this'll be the worst day of our lives.' And, you know, that was before I knew the half of it."

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