Photos

Service members read aloud the names of each person killed during the 9/11 terrorist attacks and ring a ceremonial bell for each name during a ceremony to mark the 20th anniversary of the attacks at the Pentagon, Sept. 11, 2021.

Service members ring a bell and read aloud the names of each person killed in the 9/11 attack on the Pentagon during a 20th anniversary ceremony at the Pentagon, Sept. 11, 2021.

The Towers of Light display illuminates the night sky at the Pentagon, Sept. 9, 2021, honoring those who lost their lives in the attacks of Sept. 11, 2001.

The Towers of Light display illuminates the night sky at the Pentagon, Sept. 9, 2021, honoring those who lost their lives in the attacks of Sept. 11, 2001.

A Pentagon police badge honors the 20th anniversary of 9/11 at the Pentagon, Sept. 11, 2021.

Honor guard members march during the Defense Department September 11 Pentagon Community Observance Ceremony in the courtyard of the Pentagon, Sept. 10, 2021.

A Marine Corps bugler plays taps during a 9/11 observance ceremony at the Pentagon, Sept. 11, 2019.

An American flag adorns the west wall of the Pentagon at dawn, Sept. 11, 2019, to mark the 18th anniversary of the 9/11 terrorist attacks.

Members of a Pentagon crew unfurl an American flag at dawn at the Pentagon, Sept. 11, 2019, to commemorate the 18th anniversary of the attacks.

Lighting from the benches of the National 9/11 Pentagon Memorial illuminates the dawn sky at the Pentagon, Sept. 11, 2019.

Damien Smith of Aberdeen Proving Ground's Department of Emergency Services renders honors at the Pentagon, Sept. 11, 2019, after a Pentagon crew unfurled an American flag at dawn to commemorate the 18th anniversary of the 9/11 attacks.