A body has been found in the search for a teenager who got into trouble while swimming in a river in Northumberland.
The body was discovered by Northumberland Police’s marine unit.
The force said: “Formal ID has yet to take place but we believe it to be the missing boy.
‘Stay indoors’ warning – UK weather latest
“This is a tragic update that we hoped we’d never have to give.
“His family are being supported by officers & our thoughts are with them at this awful time.”
The boy was found in a river near Ovingham and police said he was recovered after an extensive search.
UK weather – live updates: ‘Stay indoors’ warning as Met Office ‘never seen’ weather charts like this
Heatwave disruption: Schools close, hospitals cancel appointments, railways close lines and events are scrapped as UK braces for record temperatures
Heat exhaustion and heatstroke – what are the signs and symptoms and what’s the difference?
Find out the five-day forecast for where you live
Search operations started at around 4.15pm on Sunday after Northumberland Police received a report of concern for the welfare of a male who was seen in the river.
It comes as the UK is expected to reach record temperatures on Monday and Tuesday, with officials advising people to stay indoors.
This is one of a number of water-related tragedies during the heatwave, after the deaths of a 16-year-old boy in Salford Quays, Greater Manchester, and a 50-year-old man in a reservoir near Leeds.
Top tips to stay cool in the hot weather
Police in Leeds urged people to stay away from bodies of water following the death at Ardsley Reservoir on Saturday, while Greater Manchester Police issued a similar warning on Saturday.
Met Office forecasters issued a red warning for Monday and Tuesday in an indication of temperatures projected to soar above 40C.
Read more:
What a Level 4 heatwave means for the UK
Why Britain’s cities need a radical overhaul
Why climate change will make this heatwave more dangerous
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
On Sunday, College of Paramedics chief executive Tracy Nicholls warned the “ferocious heat” the UK is predicted to experience over the next few days could lead to deaths.
She told Sky News’s Sophy Ridge On Sunday programme: “This isn’t like a lovely hot day where we can put a bit of sunscreen on, go out and enjoy a swim and a meal outside.
“This is serious heat that could actually, ultimately, end in people’s deaths because it is so ferocious. We’re just not set up for that sort of heat in this country.”
The UK Health Security Agency raised its heat health warning to Level 4 – a “national emergency” – on Friday.
Level 4 is reached when “a heatwave is so severe and/or prolonged that its effects extend outside the health and social care system”