New York City is marking the 25th anniversary of the September 11 terrorist attacks on Friday with solemn ceremonies, moments of silence and heightened security across Lower Manhattan.

Nearly 3,000 people were killed in the 2001 attacks on the World Trade Center, the Pentagon and aboard United Airlines Flight 93, which crashed near Shanksville, Pennsylvania.

This year’s ceremony at the National September 11 Memorial includes an additional bell ringing and moment of silence honoring first responders, recovery workers, survivors and residents who have died from illnesses linked to the aftermath of the attacks.

Families of victims are gathering at the memorial, where the names of those killed in the September 11 attacks and the 1993 World Trade Center bombing will be read aloud.

The observance includes moments of silence marking key events from September 11, 2001. The first is at 8:46 a.m., when American Airlines Flight 11 struck the World Trade Center’s North Tower, followed by another at 9:03 a.m., when United Airlines Flight 175 hit the South Tower.

Additional moments of silence commemorate the attack on the Pentagon, the crash of Flight 93 and the collapse of the World Trade Center towers.

A major security operation is in place around the memorial and across Lower Manhattan. The NYPD said uniformed officers, counterterrorism teams, specialized units and counter-drone resources are among the security measures deployed for the commemoration.

Traffic restrictions and road closures are also in effect in Lower Manhattan, with authorities advising motorists to expect delays and use alternative routes where possible.

Mayor Zohran Mamdani is attending the Ground Zero ceremony after participating in an interfaith peace walk Thursday night. Speaking at the event, Mamdani emphasized the importance of maintaining solidarity a quarter-century after the attacks.

Vice President JD Vance and former Presidents Joe Biden, Barack Obama, George W. Bush and Bill Clinton are also expected at the New York commemoration.

President Donald Trump is marking the anniversary at the Pentagon, where another ceremony is being held to honor those killed in the attack there.

The 25th anniversary brings together victims’ families, survivors, first responders, public officials and a generation of Americans born after the attacks, as the country reflects on the lives lost and the enduring impact of September 11.

The NYPD has confirmed a significant security operation around the memorial involving local and federal agencies, while current reporting confirms the planned attendance of Vance, the four living former presidents and Trump’s separate Pentagon observance.