A 61-year-old man has become the fifth person to die in Britain's lakes and rivers this week as temperatures have soared.
Police suspect the unnamed man had a "medical episode" while trying to fetch a ball from the Blue Lagoon lake near Bletchley, Buckinghamshire.
A member of the public pulled him from the water at around 6.40pm yesterday, but paramedics were unable to save him and he was declared dead at the scene. Source: PA
His death has led to renewed warnings about the hazards of venturing into open water as the school summer holidays start amid high temperatures.
Kyrece Marshall, 13, died in the River Thames in Marlow, Bucks, after he reportedly got into difficulties trying to retrieve a ball on Tuesday.
Ten-year-old Arran Cooper, from Rutherglen, South Lanarkshire, died on Wednesday after falling into the River Orchy in the Caledonian forest reserve in Glen Orchy, Argyll and Bute, during a family holiday.
And yesterday a 16-year-old boy's body was recovered from a lake at a disused quarry in Clophill, Bedfordshire, and another boy, believed to be aged 14, was found after he disappeared in the River Great House in Hartford, Cambridgeshire.
Following the death near Bletchley, police issued further advice, urging people to go into lakes, reservoirs and other stretches of open water with caution.
Detective Inspector Matthew Darnell, of Milton Keynes CID, said: "This was a tragic incident, which has led to the sad loss of a life and our thoughts are with this man's family at this time.
"We would urge people to be aware of the hazards of getting into open water such as lakes, reservoirs and rivers, no matter how tempting it must be in the hot weather.
"Open water can contain hazards and unexpectedly cold water can catch bathers off guard.
"Inland waters can be very cold no matter how warm the weather is which can lead to cramp and breathing difficulties so we would urge people to take great care and be aware of the dangers before going in."
The RNLI also issued a safety message after a 12-year-old girl and her 21-year-old brother avoided being swept into the path of a busy shipping lane in Ramsgate, Kent, this week.
James Uren, RNLI lifeguard supervisor, said: "With the school holidays starting this week, we're expecting thousands of youngsters to flock to the beach to take advantage of the good weather.
"We want everyone to enjoy the seaside safely and the best way to do that is to visit a lifeguarded beach and swim between the red and yellow flags.
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