A 14-year-old boy is missing and believed to have drowned after getting into difficulty in the River Thames in London on the hottest day of the year.
Fours others have died while swimming in open water during the heatwave as Britain swelters, with the temperature reaching 38.1C (100.58F) today, the third hottest day on record.
It may hit 41C (105.8F) tomorrow.
The UK Health Security Agency has issued a level 4 heat-health alert – described as a “national emergency” – and the UK is under its first red extreme heat warning for a large part of England, issued by the Met Office.
The Metropolitan Police said officers were alerted just before 5pm to reports a child had entered the water at Tagg’s Island near Hampton Court in southwest London.
A widespread search was carried out involving police, paramedics and fire crews, as well as members of the public, but their efforts were unsuccessful, and at 6.40pm the rescue operation was brought to an end.
“Efforts to recover his body will continue into this evening,” the Met Police said.
UK records one of its hottest days ever – weather latest
Superintendent Richard Smith, from the South West Command Unit, said: “Despite the very best efforts of all involved, we must now sadly conclude that this young boy has died.
“I know that on days like today when temperatures are at a record high, it might look appealing to jump in and cool off in rivers, reservoirs, lakes or other open water.
“Please don’t. The dangers are real and this evening in Richmond we have seen the terrible consequences of what happens when it goes wrong.”
Meanwhile, the family of a “kind and loving” 13-year-old boy who died after getting into trouble while swimming in a Northumberland river have said they are “absolutely devastated”.
Robert Hattersley, from Crawcrook, lost his life in an incident in the River Tyne near Ovingham on Sunday.
His family said: “It is impossible to put into words the heartbreak we are feeling – Robert was so kind and loving. We are absolutely devastated by what has happened.
“He brought a smile to so many people’s faces and he will be missed by absolutely everyone who knew and loved him.”
Detective Inspector Phil Hughes, of Leeds CID, said: “This incident serves as a timely reminder about the dangers of swimming in open water.”
Also, a 16-year-old boy died after getting into difficulty earlier today in Bray Lake, near Maidenhead, in Berkshire.
Superintendent Michael Greenwood, the local policing area commander for Windsor and Maidenhead, said it was an “absolute tragedy”.
Emergency services have issued urgent appeals for people to stay out of dangerous waterways and reservoirs.
A 50-year-old man lost his life after getting into difficulty at Ardsley Reservoir, between Leeds and Wakefield. A body, thought to be his, was found on Sunday.
A 16-year-old boy died after he was seen struggling in the water at Salford Quays, Greater Manchester, on Saturday.
Temperatures rose to 38.1C in Santon Downham, Suffolk, on Monday and the mercury topped 37C in a number of other places.
Rail services were reduced and trains were forced to travel more slowly amid the risk of buckling rails, and people appeared to heed warnings to work from home as traffic, train and Tube passengers were down on the previous Monday.
There are also warnings of pressures on hospitals from the extreme temperatures, and concerns that ambulance services would face rising numbers of calls as the heat peaks on Tuesday afternoon.
The existing UK temperature record of 38.7C (101.7F), which was registered in Cambridge in 2019, looks almost certain to fall on Tuesday.
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How to stay safe in the heat – official advice
Keep out of the sun between 11am and 3pm and avoid physical exertion
Drink plenty of fluids and avoid excess alcohol
Close curtains in rooms that face the sun
Never leave anyone in a parked car – and check in on elderly and vulnerable neighbours
Walk in the shade, apply sunscreen and wear a wide-brimmed hat
Check medicines can be stored according to instructions – and check that your fridges, freezers and fans are working properly
Wales has provisionally recorded its hottest day on record, with the temperature reaching 37.1C in Hawarden, Flintshire, beating the previous record for the nation – 35.2C – which was also set in Hawarden, in 1990.
Tuesday is predicted to be even hotter in the UK, with temperatures possibly reaching a “crazy” 41C in Yorkshire and Lincolnshire.