US President Joe Biden has tripped and fallen while handing out diplomas at a graduation ceremony for the US Air Force Academy in Colorado.
Mr Biden, who is the nation’s oldest serving president at 80, was helped back up to his feet and appeared to be unhurt.
The president had been standing for about an hour and a half to shake hands with each of the 921 graduating cadets.
The White House communications director said earlier “he’s fine”.
“There was a sandbag on stage while he was shaking hands,” Ben LaBolt wrote on Twitter after Thursday’s fall.
“I got sandbagged,” the smiling president joked to reporters as he arrived back at the White House that evening.
A White House press pool report earlier said Mr Biden had tripped on a black sandbag while moving on stage.
Footage of the incident shows Mr Biden appearing to point at one of two sandbags used to prop up his teleprompter as he was helped up by an Air Force official and two members of his Secret Service detail.
He was seen walking back to his seat unassisted and later jogging back to his motorcade when the ceremony ended shortly after the accident.
Critics have said Mr Biden is too old to run for a second term as president.
Recent polls suggest a majority of US voters are concerned about his advanced age. He would be 82 at the start of a second term if he wins.
This fall, in addition to previous stumbles from his bicycle and on the way up the Air Force One stairs, could add to those concerns.
Former President Donald Trump, the Republican frontrunner to face Mr Biden in the 2024 White House election, reacted to the incident from a campaign event in Iowa, saying “the whole thing is crazy”.
“I hope he wasn’t hurt,” said Mr Trump, 76, who has often poked fun at Mr Biden’s age. “That’s not inspiring.”