PEOPLE are being warned to stay safe on the coast after a young man was feared to have drowned whilst swimming.

The 21-year-old got into difficulties swimming with two friends near Durdle Door on Wednesday.

With the weather expected to deteriorate over the coming days people are being urged to take extra care along the coast.

Coastguards have issued a warning to residents and visitors to avoid swimming in ‘dangerous’ and ‘cold’ waters at this time of year.

The missing man, who is believed to be from Portsmouth, had travelled to Durdle Door for the day with two friends, aged 21 and 22.They were swimming together when he got into difficulty and his two friends headed back to shore to get help.

Two other men men have been hailed as heroes for trying to rescue the stricken swimmer.

The brave duo dived into rough and cold waters when the 21-year-old came into difficulty.

The heroic men, who are believed to be from London and aged in their 30s, had been on the beach before they leapt into action.

Despite their efforts, they were unable to get the ‘unresponsive’ swimmer back to shore without risking their own safety.

A major search and rescue operation was launched to find the missing man on Wednesday night involving lifeboats, helicopters and search teams.The Portland Coastguard Rescue helicopter continued the search until 11.30am yesterday morning.

Coastguard Robert Sansom, Weymouth sector manager, said: “Even when the water looks benign it can be dangerous at this time of year and especially to visitors who are not familiar with the tides.

“We do not want to put people off trying to save others but we would urge people not to put their lives at risk and dial 999.”

He added: "We continued the search on Thursday morning at 8am covering 20 miles of coast line where we suspect he might have been. “The search has now ended until any further sighting.”

Mike Branagan, coast watch assistant at Portland Coastguard said: “The efforts of the two men who tried to save this man should be praised but they made the right decision to return to shore as their own safety was at risk.”

Search teams included Lulworth and Wyke coastguards and Portland Coastguard helicopter, together with a Navy helicopter.

The search stretched from Lulworth Cove to Bowleaze Cove.

Speaking on Wednesday, Portland Coastguard Watch Manager Ros Evans said: “Everyone involved did everything they could to rescue this person but unfortunately this is increasingly looking like a tragic accident.”

The events followed a drama in the same area a few hours earlier when a man was treated for hypothermia after going swimming. The sea was said to be ‘very rough’ at the time.

DORSET Police are now treating the incident as a missing person investigation.

A spokesman said: “At 4.20pm on Wednesday Dorset Police received a request for assistance from the HM Coastguard concerning three men in their 20s that had got into difficulties while swimming at Durdle Door.

“On the police arrival two swimmers had made it back to shore safe and well but one had gone missing out at sea.

“The police helicopter assisted HM Coastguard in a search of the area until darkness when the search was stopped.”

HM Coastguard resumed the search the next morning.