Hegseth was accompanied by his wife, Jennifer Hegseth, Chief of Staff Ricky Buria, Deputy Chief of Staff Patrick Weaver and senior adviser Tami Radabaugh. The footage does not make clear who was laughing, and accounts of the circumstances differ. Some describe the group on the memorial's steps taking photographs and talking after a Veterans Day event. Others describe loud laughter during a photo opportunity, or talking and laughing while the group walked away from the tomb. The sentinel has not been identified.

Pentagon spokesman Sean Parnell said Hegseth and the Department of Defense have "always honored" the sacrifices of the military. He said the soldier "correctly and respectfully reminded everyone to maintain decorum."

Critics took a harsher view. Adam Kinzinger, a former Republican congressman from Illinois and an Air Force veteran, and Rep. Shontel Brown, an Ohio Democrat, condemned the behavior as "abhorrent" and a "disgrace." Moe Davis, a retired Air Force colonel, called it inappropriate and described Hegseth's conduct as "daily dishonor and disgrace."

The episode came days after Hegseth survived an impeachment attempt in the House of Representatives. He is a former Army National Guard soldier, and his tenure has included the war with Iran and strikes on boats suspected of carrying drugs, which he has defended. Democrats, who recently won control of both chambers of Congress, have promised to investigate his leadership of the Pentagon.

The Tomb, dedicated in 1921 on a hill overlooking Washington, holds the remains of unidentified American service members, including one from World War I. Arlington National Cemetery calls it a "national shrine to the honored dead," and federal regulations prohibit disrespectful conduct there. Sentinels are volunteers from the 3rd U.S. Infantry Regiment, known as the Old Guard, and fewer than 20 percent of applicants are accepted. They walk a 21-step patrol in honor of the 21-gun salute, and the Old Guard has kept the Tomb under continuous guard since April 1948.