A man who ran into a stream in the middle of the night before collapsing has died.
Firefighters had to use specialist equipment to cut through fences to reach the man, who passed out after crossing the Silk Stream river in Hendon early on Wednesday morning (December 20).
He was taken to hospital but died later that morning.
The Metropolitan Police say officers became aware of a car in The Hyde at about 1.40am on Wednesday.
A man ran from the car and into the Silk Stream, which feeds into Welsh Harp Reservoir, and made his way to the far bank, where he was then seen to collapse, Scotland Yard said.
Officers did not follow him into the water, but went around the water's edge to try to reach him.
But the area where the man collapsed was enclosed by fences and officers could not reach him.
London Fire Brigade and London Ambulance Service were called and fire crews used specialist equipment to reach the man so first aid could be given.
According to Accuweather, the temperature was around 4C.
Paramedics then took the man, who was believed to be in his late 40s, to hospital in a critical condition.
He died later that morning (December 20).
His next of kin have been informed and are being supported by specialist officers.
Witnesses reported a heavy police presence during the day by the Sainsbury's car park at the Hyde Estate, which is right next to the water.
As in all cases of death following police contact, the Met's Directorate of Professional Standards have been informed. The Independent Office for Police Conduct has also been notified.
The Met says the officers involved are being supported following the traumatic event.
Commander Owain Richards of the Met’s Frontline Policing said: "This is a very sad incident and my thoughts and condolences go out to the man's family and all those affected.
“It is only right and proper that all the circumstances surrounding this incident are fully investigated and the Met police will fully co-operate with any inquiry.
“In the meantime, we will be speaking to our partners and the community to provide reassurance and provide as much information as we can."
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