President Obama paid an emotional visit here Thursday to mark the death of Osama bin Laden, observing a moment of silence at ground zero and telling firefighters that U.S. forces who executed the mission "were doing it in the name of your brothers that were lost."
The president also met privately with 9/11 families for nearly an hour during his trip to the city four days after the terror mastermind was killed in Pakistan.
Obama made no public remarks when he laid a wreath at the site of the Sept. 11 memorial, which is now under construction, before observing a moment of silence with his head bowed. He greeted first responders there, along with several victims' relatives.
Before his visit to the site where nearly 3,000 people were killed, Obama stopped at a midtown firehouse that lost 15 members in the attacks nearly 10 years ago.
There, the president told firefighters that the killing of bin Laden sends the message that "when we say we never forget, we mean what we say."
"So it's some comfort, I hope, to all of you to know that when those guys took those extraordinary risks going into Pakistan, that they were doing it in part because of the sacrifices that were made in the States," he said. "They were doing it in the name of your brothers that were lost."
Obama joined former Mayor Rudy Giuliani and Fire Commissioner Salvatore Cassano for lunch with firefighters. He also visited a police precinct in Tribeca before heading to ground zero.
"We've never forgotten the tragedy. We've never forgotten the loss of life," he told police officers. "What we did on Sunday was directly connected to what you do every single day."
Onlookers lined the streets near the World Trade Center site in Lower Manhattan, some applauding and cheering, and crowds outside the firehouse chanted "U-S-A, U-S-A" as Obama arrived.
Firefighter Joe Ceravolo, who cooked a lunch of shrimp, veal and eggplant Parmesan for the president, said the firehouse "just wanted to tell him we thank him for what he did on Sunday, and all the troops... If it weren't for them, we'd still be chasing this guy."
At ground zero, New Yorkers waited hours for his arrival.
Rose Giovinazzo, whose brother, Martin Giovinazzo, was killed in the attack, said at the site that the president's visit is significant.
"Today does bring some closure," she said.
New York City has been on high alert ever since the stunning announcement on Sunday that bin Laden had been killed. There was extra security throughout the day for the president's visit.
"We have the NYPD out there protecting us," Mayor Bloomberg said Wednesday. "I feel as safe today as I felt last week, and I think all New Yorkers should."
Law enforcement sources said a man was taken into custody near ground zero, but the situation was not believed to be serious. He was not armed and may have been drunk, sources said.
Obama has visited ground zero before, but not as president. His last public appearance there was as a candidate in 2008.
News of his visit today evoked comparisons this week to former President George W. Bush's appearance at the rubble pile in the days after the World Trade Center was hit. Obama invited Bush to accompany him this time, but the former president declined.
After announcing on Wednesday that the president had decided not to release graphic death photos of bin Laden, press secretary Jay Carney said in a briefing on Air Force One Thursday that he was not aware of any officials bringing the photos to share with family members, in case they wanted to see them.
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