A man has died following an open water swimming session at a lake in a country park.
The 55-year-old failed to return from a session at Hetton Lyons Park, in Hetton-le-Hole near Houghton-le-Spring, a police spokesperson said.
Police were called to the country park at about 11:30pm on Wednesday 31 May and a body was found following a search.
An investigation is underway into the circumstances surrounding his death.
A Northumbria Police spokesperson said: "At around 11.30pm last night (Wednesday) we received a report of concern for the welfare of a 55-year-old man, who had not returned home from an open water swimming session in Hetton Lyons Park.
"Police attended the area, and assisted by colleagues from the National Police Air Service (NPAS) and Tyne and Wear Fire and Rescue Service (TWFRS) carried out a full and thorough search of the area.
"Sadly those searches led to the discovery of the body of a man. His family have since been notified and are currently being supported by specialist officers.
"An investigation into the circumstances surrounding his death are ongoing and police officers remain in the area at this time."
A Tyne and Wear Fire and Rescue Service (TWFRS) spokesperson said: "We can confirm we supported a multi-agency search for a missing person at Hetton Lyons Park in the early hours of this morning.
"Our search and rescue team was deployed to the location and sadly the body of a man was later recovered from the water. The thoughts of everyone at Tyne and Wear Fire and Rescue Service are with the family and friends of the man in question."
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