The United States on Friday marked the 25th anniversary of the September 11, 2001 terrorist attacks, with solemn ceremonies held in New York, Washington and Pennsylvania to honour the nearly 3,000 people killed in the attacks.

In New York, families of victims gathered at the World Trade Center memorial to read the names of those who died when hijacked planes crashed into the Twin Towers. Moments of silence were observed at key times corresponding to the attacks and the collapse of the towers.

President Donald Trump is commemorating the anniversary at the Pentagon, where one of the hijacked aircraft struck the building. A separate ceremony is being held at the Flight 93 National Memorial in Shanksville, Pennsylvania, where passengers and crew fought back against hijackers before the plane crashed into a field.

The anniversary is also being used to remember first responders and rescue workers who died from illnesses linked to toxic exposure following the attacks. The tragedy reshaped US foreign and domestic policy, leading to the so-called war on terror, the creation of the Department of Homeland Security and the US-led wars in Afghanistan and Iraq.

Twenty-five years later, the attacks remain a defining event for Americans, including a growing generation too young to remember the day. Across the country, communities are holding memorial services and tributes to honour those killed and reflect on the lasting impact of September 11.