Two seriously injured crew members have been airlifted to safety from a stricken British yacht off the coast of Cornwall.

The two casualties were taken by helicopter to RAF St Mawgan where they emerged wrapped in blankets.

They were immediately assessed by paramedics from the West Country Ambulance Service, before being taken to the Royal Cornwall Hospital in Truro.

The rescue mission was launched after the 65-foot yacht Persuader, with seven people on board, became dismasted and holed in force nine gales on Tuesday afternoon.

Trying to drop rescuers on to the deck and then take casualties off the boat is a very hazardous operation

Coastguard Mark Clark

Two American MH-35 long-range helicopters - known as "Jolly Green Giants" - from RAF Mildenhall in Suffolk, a Nimrod aircraft and a refuelling Hercules airtanker were sent to the scene.

At first light, rescue crews began attempts to winch the two men from the Persuader more than 400 miles south-west of Land's End.

Poor weather and rough seas severely hampered the rescue with the yacht pitching in 25-foot seas.

Two winchmen were eventually lowered on to the vessel but one of the helicopters had to return to base when it developed problems with its winch.

The other helicopter managed to lift the injured crew members and their rescuers at 0830 BST.

'Pitching and yawing'

The casualties are being taken to RAF St Mawgan, in Cornwall where they will be properly assessed, but both are thought to have suffered broken ribs and one has internal injuries.

Mark Clark, from the Falmouth Coastguard, said: "The weather was pretty ferocious and has made this a difficult rescue.

One of the injured men is taken for treatment

"The yacht was pitching and yawing in 25-foot seas so trying to drop rescuers on to the deck and then take casualties off the boat was a very hazardous operation."

The Guernsey-registered Persuader was en route to the UK from the Caribbean via the Azores when she ran into difficulties.

Fuel level

The emergency beacon belonging to the yacht, began transmitting from an area 480 miles south-west of Land's End on Tuesday, while the yacht was out of range for UK rescue teams.

Watch officer Terry Collins told BBC News Online the yacht's skipper had confirmed the engine was in good order and there was enough fuel for the remaining five crew members to continue on to Falmouth.

The crew of the helicopter, which refuelled six times during the long mission, was said to be exhausted and have been flown back to their base in Suffolk.