Two pro-Palestinian demonstrators have thrown red powder on Tower Bridge - just moments before leading runners in the London Marathon raced past.
The protesters were arrested on suspicion of causing a public nuisance and remain in custody, said the Metropolitan Police.
A video shared by Youth Demand, which is calling for a trade embargo on Israel, shows two people jumping over a barrier that separates spectators from the race course.
The pair, wearing t-shirts that say "Youth Demand: Stop Arming Israel", are then seen standing in the middle of the road on the bridge.
They throw red powder in the air as an official marathon car goes past displaying the race time.
A motorbike with a cameraman on board continues along the route, while a second motorbike stops and one of the race officials gets off and pushes the pair out of the way, just before the men's elite runners pass.
Several police officers then jump over the barrier and detain the pair, the footage shows.
There appeared to be no impact on the marathon.
More than 56,000 participants were expected to take part in the 26.2-mile race through the capital.
Sabastian Sawe of Kenya won the men's elite race in a time of two hours, two minutes and 27 seconds, while Ethiopia's Tigst Assefa shattered the women's-only world record in two hours, 15 minutes and 50 seconds.
Assefa beat the previous best of two hours, 16 minutes and 16 seconds set last year in London by Kenyan Peres Jepchirchir.
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The Metropolitan Police said in a statement: "At around 10.38am, two protesters from Youth Demand jumped over barriers at Tower Bridge and threw red paint on to the road.
"Marathon event staff intervened to remove the protesters from the path of the men's elite race which was able to pass unobstructed."
The force added that they were "quickly supported by police officers who arrested the protesters on suspicion of causing a public nuisance".
The Met said the paint "appeared to be chalk-based" and was not expected to "present a hazard to runners yet to pass this point".
(c) Sky News 2025: Protesters throw powder on Tower Bridge during London Marathon
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