President Biden was uninjured after falling on stage congratulating the last of the Air Force Academy graduates at a commencement ceremony Thursday.

Biden, who delivered the commencement address and stayed on stage for a couple of hours as diplomas were awarded, could be seen in a video stumbling and falling. He was helped up by Air Force officials and pointed at a sandbag that appeared to be the cause of his tumble.

“He’s fine. There was a sandbag on stage while he was shaking hands,” White House communications director Ben LaBolt tweeted.

Footage of the fall quickly circulated on social media, with Republican officials among those sharing it.

At 80, Biden is the oldest individual ever to serve as president, and his age and fitness for office is likely to be a key factor as he runs for reelection in 2024.

Biden has previously acknowledged that it’s fair for voters to wonder about his age. But he has responded by saying that he remains up for the job, and those who are unsure should simply watch him and the rigorous schedule he keeps.

“The only thing I can say is they’re going to see a race, and they’re going to judge whether I have or don’t have it,” Biden said in April after announcing his reelection bid.