A man has died after becoming trapped underwater at a weir on the River Derwent.
Crews were called to the river off Raynesway, Derby, at 18:59 BST on Saturday after reports of three men in the water.
Derbyshire fire service said a 25-year-old man had "become trapped under the water on the weir".
Station manager Paul Green said water rescue teams located him but "sadly the man has passed away".
He said: "Our crews were mobilised to assist three males who were in the water, at an area known locally as Pebble Beach along the River Derwent.
"One of the group had got into difficulty and had become trapped under the water on the weir.
"Firefighters and specialist swift water rescue teams worked together to locate the man before handing him into the care of paramedics. Sadly the man has passed away."
Derbyshire Fire & Rescue Service warned people of the dangers of open water as UK temperatures hit record highs.
Mr Green added it was "a tragic incident" and "thoughts and sympathy are extended to the family and friends of the deceased at this extremely sad and distressing time".