He was in the water quite a while until he was dragged under and they never saw him again

Peter Dee, coastguard

Inspector Jon Perry, of Devon and Cornwall police, said the police were considering the man missing, feared dead.

"We are assuming he is lost at sea and we are having to treat it as the worst case scenario," he said.

The trapped group had been out drinking on Saturday night and apparently headed for the beach to continue their party, then became trapped by the tide.

One managed a perilous 150-foot climb up a steep cliff, strewn with loose stones, to raise the alarm.

Rope rescue

The other 10 people trapped in the cave were hauled to the top of the cliff by rescue teams, and taken to hospital by ambulance.

Two rescue teams had abseiled down the cliff in increasingly dangerous weather conditions, to bring up the group one-by-one.

A man climbed the 150-cliff to call for help

But there was no sign of the twelfth member of the group.

He had last been seen standing on a rock between 0830 and 0900 GMT on Sunday and then a wave swept him out to sea.

Coastguard Peter Dee said the missing man was believed to be a strong swimmer.

"He was in the water quite a while until he was dragged under and they never saw him again," he said.

'Terrible' weather

"To stay afloat in those conditions is virtually impossible. The sea just doesn't forgive you."

Winds of 45 mph forced a Royal Navy search and rescue helicopter to return to the Culdrose air station, and two inshore lifeboats were ordered to return to port.

Waves hitting the beach were between six and eight feet high.

Falmouth coastguards said rescue teams continued with the search of the shoreline at low water.

A coastguard spokesman said the climb by one of the party to raise the alarm from a public telephone box would have been incredibly difficult.

He said: "The weather was terrible. It was a pretty impressive climb."