Defence Secretary Pete Hegseth and his group were publicly reprimanded by a US Army sentinel at the Tomb of the Unknown Soldier on Wednesday, after laughter and talking broke the silence at one of America's most sacred war memorials during a Veterans Day visit.

The incident took place at Arlington National Cemetery in Virginia, after a ceremony at which President Donald Trump laid a wreath in honour of fallen service members. Hegseth, his wife Jennifer, and several senior aides had gathered at the tomb for photographs after the ceremony.

As the group began to walk away, someone in the party was heard laughing. The sentinel on duty stopped his patrol, turned to face the group and called out: "All visitors will maintain an atmosphere of silence and respect at all times." The exchange was captured on the live network pool feed stationed at the tomb and was later broadcast by CNN.

Hegseth made no verbal acknowledgement of the reprimand. According to NBC News, he glanced back over his shoulder and continued up the stairs. It remains unclear who in the group laughed, or whether Hegseth himself made any noise.

Pentagon says soldier acted correctly

Chief Pentagon spokesman Sean Parnell said the soldier had acted properly. "The Secretary and the entire Department have always honored — and will always honor — the sacrifices our military men and women have made to keep America safe," Parnell said. "While commemorating this solemn day, a soldier correctly and respectfully reminded everyone to maintain decorum."

Those with Hegseth at the tomb included his chief of staff, Ricky Buria, his deputy chief of staff, Patrick Weaver, and senior adviser Tami Radabaugh. CBS News, which also broadcast the footage, noted that it is not unusual for sentinels to reprimand visitors who break the rules of silence at the memorial.

A memorial guarded around the clock

The Tomb of the Unknown Soldier marks the final resting place of unidentified American service members killed in battle, beginning with a soldier from the First World War. Soldiers of the 3rd US Infantry Regiment, known as The Old Guard, have guarded the tomb around the clock, in all weathers, since 1948. Visitors are told to speak quietly and to observe proper standards of decorum, and the sentinels are trained to deliver the same instruction to any visitor who disturbs the silence, regardless of rank.

The reprimand came at a difficult moment for Hegseth. A day earlier, the House of Representatives had voted to derail articles of impeachment filed against him by outgoing Republican Representative Thomas Massie, who accused him of carrying out unlawful orders, including waging war in Iran without congressional approval. The video of the sentinel's rebuke spread quickly online, with supporters of the guard praising him for treating a cabinet secretary like any other visitor, and critics of the administration calling the episode embarrassing.

The Pentagon has given no indication that any action will be taken against the soldier, and the department's own spokesman has publicly backed him.

Sources: CNN and CBS News.