Emergency services are searching for a 13-year-old boy who got into difficulty in the sea.
The boy was swimming off the coast of Hornsea, East Yorkshire, on Tuesday evening.
HM Coastguard, Yorkshire Ambulance Service and Humberside Fire and Rescue Services, Humberside Police officers were all deployed to the area of the South Promenade at around 6pm.
Chief Superintendent Phil Booker, of Humberside Police, said: "After receiving the report, officers were immediately deployed alongside other emergency services and upon attending, it was discovered that a 13-year-old boy had reportedly got into difficulty whilst swimming in the water.
"Our priority now is to find the boy, and members of the public can expect to see specialist Police Search Advisors (POLSA), along with our Marine Unit and drone pilots, who have also been deployed to conduct an extensive search and rescue operation to locate him.
"We would urge people to please avoid the area where possible to allow emergency services to work efficiently and safely, and refrain from speculating on the circumstances of the incident.
"Our enquiries continue to ascertain the full circumstances around the report, and we would ask anyone with any information that may assist us, to please speak to the officers in Hornsea, or contact us via our non-emergency number 101."
It comes as the UK experienced its latest heatwave, with temperatures rising above 30C in parts of the country earlier this week.
Met Office monthly temperature records for the UK were broken in both May and June this year, while Monday marked the 20th day of 2026 when temperatures of 32C or higher were recorded, exceeding the previous record of 19 days set in 1995.
Meanwhile, England and Wales saw their driest July on record, according to provisional Met Office figures.
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'A very real risk'
On Monday, a 14-year-old boy drowned in London after entering the Millwall Outer Dock near East Ferry Road.
The Met Police's Detective Superintendent Oliver Richter said: "As the warm weather continues, I would urge everyone to remember that open water can present serious dangers. Please only swim in designated areas and take the time to speak with children and young people about staying safe around water."
The RNLI issued a water safety warning in May following a series of water-related deaths.
The organisation warned that "while the air temperature is warm, the seas are still cold and cold water shock remains a very real risk".
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