A man has died after taking part in a swimming challenge in a lake.
The 52-year-old was taken to hospital by air ambulance following the incident during the Great North Swim in Windermere, Cumbria Police confirmed.
The force said: "At 4.40pm today police at the event were alerted to a man who was taken by air ambulance to the Cumberland Infirmary, as a result of a medical emergency.
"The man, aged 52, from Wallington, sadly died."
The man's death is not being treated as suspicious and the coroner has been informed, police added.