US President Joe Biden has fallen off his bike while cycling near his holiday home in Rehoboth Beach, Delaware.
The 79-year-old tumbled after his foot got stuck in the pedal toe cage as he tried to dismount in order to chat to the waiting crowd of around 30 people.
Onlookers gasped as they saw him fall. Secret Service agents rushed to the president's aid.
Biden swiftly got up, telling onlookers "I'm fine", as agents told the crowd to back up. There were no signs of the president suffering any cuts or grazes.
The president made light of the incident, joking with the crowd after getting up. Running the country was like any other job, he told one well-wisher.
"When you are president, will you remember me?" he asked one small child.
Biden had set off 11 minutes earlier accompanied by his security detail, breezing past members of the press pool unaccompanied by the First Lady, Jill Biden.
She had left with members of her own security detail about seven minutes ahead of the President.
The Bidens, who celebrated their 45th anniversary on Friday, are understood to be keen cyclists, often taking to their bikes while in Delaware.
The White House played down the incident.
An official said: "As the President said, his foot got caught on the pedal while dismounting and he is fine.
"No medical attention is needed. The President looks forward to spending the rest of the day with his family."
Although the incident was little more than a minor tumble, it will inevitably rekindle concerns about Biden.
Earlier this month he stumbled as he boarded Air Force One at Andrews Air Force Base before flying to California but was fine.
Others were not so lucky.
Secretary of State John Kerry broke his leg when his bike hit a kerb in the French Alps in 2015. He needed surgery and months of recovery – at a time when he was negotiating the Iranian nuclear deal.
Biden's most spectacular mishap came in December 2020 when he fell over chasing his dog Major, which resulted in the then president-elect having to wear a medical boot for several weeks.
Opponents have been swift to seize on even the slightest misstep to question his physical fitness and ability to seek a second term.
And even allies have raised questions about whether Biden, who will be 82 at the time of the next presidential inauguration, should run again.
David Axelrod, a former adviser to Barack Obama, was among those voicing alarm.
"The presidency is a monstrously taxing job, and the stark reality is the president would be closer to 90 than 80 at the end of a second term, and that would be a major issue," he reportedly said, according to the New York Times.
In December, Biden said he would run for re-election if he was in good health.
"I'm a great respecter of fate. Fate has intervened in my life many, many times," he said. "If I'm in the health I'm in now, if I'm in good health, then, in fact, I would run again,"
Biden's latest tumble gave reporters the opportunity to draw the president into the briefest of impromptu press conferences.
The president said he would be talking to the Chinese leader Xi Jinping soon.
Asked about trade tariffs, he responded: "I'm in the process of making up my mind."
On guns, he hailed legislation passed in Delaware.
"In Delaware, I am. Did you see what they did in Delaware? Passed an assault weapons ban. They did what I did years ago. But I am happy with the progress."
He then set off.