A man died after trying to save his family who got into difficulty in the water at a Cornish beach over the bank holiday weekend. Today saw the hottest day in May on record as temperatures reached 35.1C at Kew Gardens in London, as the UK's week-long heatwave continues. While thousands of Brits flocked to beaches and popular swimming spots over the long weekend, five people tragically lost their lives after getting into trouble in the water. One man, in his 60s, suffered a 'cardiac arrest in the sea' after heroically trying to help two relatives at Tregirls Beach, near Padstow, at around 3.50pm yesterday. The family members were brought to safety by members of the public, before the man was pronounced dead at the scene. Four teenagers also died in separate water-related incidents over the weekend. The deaths of three boys and a 15-year-old girl were confirmed by police forces in Lincolnshire, West and South Yorkshire, as well as Warwickshire. A 13-year-old boy died in hospital after being pulled from the water at a popular swimming spot in Halifax, West Yorkshire, at around 3.20pm yesterday. Just hours later, the body of a 15-year-old girl was recovered from a lake at a country park in Warwickshire. South Yorkshire Police also responded to reports that a teenage boy had gone into the lake at Rother Valley County Park in Rotherham and had not re-emerged. Emergency services recovered his body in the early hours of this morning. It came a day after 15-year-old Declan Sawyer drowned at Swanholme Lakes in Lincoln at around 2.30pm on Sunday. A view of the beach as people enjoy the hot weather in Brighton, East Sussex Declan Sawyer, 15, drowned at Swanholme Lakes in Lincoln at around 2.30pm on Sunday A major emergency response was called to Leadbeater Dam after reports of a swimmer in difficulty