Seven teenagers have died in water-related incidents in the UK over the heatwave, with another dying in Ireland and a 60-year-old man dying in Cornwall.
A body was found earlier by rescuers searching for a teenager who went missing while swimming in open water in Cheshire.
Specialist divers and helicopter crews were looking for the 17-year-old boy, who was last seen in the water at Pickmere Lake, near Northwich.
Formal identification has not yet taken place. However, Cheshire Constabulary said the body was believed to be that of the missing teenager.
The death was not being treated as suspicious, the force added.
It's the ninth known such incident - and eighth involving young people - in the UK and Ireland during the recent heatwave, which has seen record-breaking temperatures for this time of year.
Britain saw five days of unseasonably hot weather for spring from Friday, with Tuesday seeing the hottest ever May day recorded in the UK, breaking the record for a second day in a row.
As it happened: Hottest ever May day
At around 1.30pm on Wednesday, Hampshire and Isle of Wight Constabulary said that the body of a teenager was found in Hawley Lake near Blackwater.
The force said: "Formal identification has not taken place, but the family of the teenager have been notified."
The first reported incident involved 15-year-old Declan Sawyer, whose body was recovered after he got into difficulty after entering Swanholme Lakes in Lincoln on Sunday.
Declan's father Carl paid tribute to a "funny and outgoing young man who loved his fishing and his football" in a statement via police, and urged parents, friends and family to "make their children aware of the dangers surrounding water".
Teens found in Halifax, Warwickshire, Ribchester
On Monday afternoon, a 13-year-old boy died after getting into difficulty at Leadbeater Dam, near Halifax, West Yorkshire.
A West Yorkshire Police spokesperson said the teenager was pulled from the water and taken to hospital, where he was pronounced dead.
That same afternoon, a man in his 60s died of cardiac arrest after entering the sea at Tregirls Beach, Padstow, to help two family members who had gotten into difficulty, Devon and Cornwall Police said.
The two family members were brought to safety by members of the public.
On Monday evening, the body of a teenage girl was recovered from the water at Kingsbury Water Park, Warwickshire.
According to Lancashire Constabulary, a 12-year-old boy also died on Tuesday after he got into trouble while swimming with friends in the River Ribble at Ribchester.
The force received a report shortly after 2pm that the boy had entered the water. A body, which police believed to be the boy's, was recovered from the river at about 7.50pm.
And in the early hours of Tuesday, the body of a teenager was recovered from the water at Rother Valley Country Park near Sheffield after he went missing, South Yorkshire Police said.
A specialist search operation was launched following reports at 6.50pm on Monday that the boy entered the water, but had not been seen getting out.
In County Dublin, Ireland, another teenager died while swimming in the sea over the weekend, officials confirmed on Tuesday.
Girl in critical condition in Merseyside
It comes as Merseyside Police appealed for information after a 15-year-old girl was left in a critical condition after getting into difficulties at Formby Beach on Monday.
The force said emergency services were called to the beach at about 3.30pm, and that the girl was being treated at Alder Hey Children's Hospital.
Detective Chief Inspector Alan Nuttall said: "We know that Formby Beach was exceptionally busy on Bank Holiday Monday but I would appeal for anyone who witnessed this incident or has any information which could assist our inquiries to get in touch as a matter of urgency."
He added that officers believed "the girl got into difficulties in the water and members of the public came to her aid".
(c) Sky News 2026: Seven teenagers die after getting into difficulty in water during UK heatwave - as well as man in 60s a
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