The body of a man has been pulled from the River Thames near Hampton Court.
The emergency services received calls about a person in the water at 4.12pm on Sunday.
The body of the man, believed to be in his early 20s, was pulled from the river around 10.30pm on Sunday night by police divers.
His next of kin have been informed, the Metropolitan Police said.
Superintendent Richard Smith, Acting Commander for the South West, said: “Our thoughts go out to the young man who has lost his life.
“Our officers worked incredibly hard with partner agencies but despite a rapid response he could not be rescued.”
During the recent heatwaves police have warned the public about the dangers of large bodies of water, and several people have died.
“We recently saw another tragic incident in which a young boy died after entering the Thames at Tagg’s Island, Sup. Smith added.
“I must again sadly reiterate the dangers the water poses.
“It may look appealing but the danger and risk of loss of life is incredibly real. Please do not enter the water at any point. The consequences are enormous and we do not want to see any more families having to suffer such terrible news.”
Following a long stretch of hot weather the UK is now braced for several days of thunderstorms – but the change in weather is likely to bring more danger rather than relief, meteorologists have warned.