WASHINGTON (AP) - President Donald Trump will mark the solemn 17th anniversary of the Sept. 11 attacks by participating in a ceremony at the 9/11 memorial in Pennsylvania on Tuesday, the White House said.
First lady Melania Trump will accompany the president to the remembrance in Shanksville.
Nearly 3,000 people were killed on Sept. 11, 2001, when hijackers flew commercial airplanes into New York's World Trade Center, the Pentagon and the Pennsylvania field in what was the worst terrorist attack on U.S. soil.
The 40 passengers and crew aboard United Airlines Flight 93, which crashed in Pennsylvania after leaving Newark, New Jersey, en route to San Francisco, are credited with thwarting a strike on the U.S. Capitol.
Trump observed the somber anniversary for the first time as president last year.
He and the first lady, surrounded by aides and administration officials, led a moment of silence on the White House lawn at the exact time that hijackers, executing a plot orchestrated by al-Qaida leader Osama bin Laden, had rammed the first of two airplanes into the Twin Towers.
Trump also participated in last year's 9/11 observance at the Pentagon.
A native New Yorker, Trump has a mixed history with 9/11. He frequently uses the terrorist strikes to praise the city's response but has also made unsubstantiated claims about what he did and saw that day.
Trump often lauds the bravery of New York police officers, firefighters and other emergency responders who rushed to the crumbling Twin Towers as an example of the city's resilience. But he has accused fellow Republican George W. Bush, who was president on 9/11, of failing to keep Americans safe.
Trump has also made dubious claims about Sept. 11. He has said when talking about Muslims that "thousands of people were cheering" in Jersey City, New Jersey, across the Hudson River from lower Manhattan, as the towers collapsed. There is no evidence in news archives of mass celebrations there by Muslims.
Trump has also said he lost "hundreds of friends" in the attack and said he helped clear rubble afterward.
Trump has not provided names of friends who perished in the attack, but has mentioned knowing a Catholic priest who died while serving as a chaplain to the city's fire department.