TWO men who survived 24 hours trapped on a Severn sandbank in freezing fog were plucked from the rising tide in the nick of time by SARA rescuers on Tuesday.

The pair, who are believed to come from Thornbury, north of Bristol, ran aground at 4pm on Monday off Aylburton and contacted the Swansea Coastguard via VHF radio. Originally they were thought to be safe and planned to wait for high tide, but conditions deteriorated rapidly as night set in.

SARA's Sharpness crew were scrambled at 3.10am in freezing conditions and dense fog but failed to find the 16ft boat, Cross Winds, and stood off for fear of running into it or grounding themselves.

"I was frozen like concrete and so were my crew," said the Sharpness crew master, adding his main fear was that the men would need immediate treatment for exposure and hypothermia.

Steve Jones, Swansea Coastguard watch manager, reported as the drama unfolded: "The coastguards and lifeboats have been searching for the men and throughout the period of high tide. Unfortunately, tidal conditions mean that the inshore lifeboats cannot continue their search.

"We are still in contact with the two men, who are now very tired, having been awake in freezing fog throughout the night. They are confident that they are in a relatively safe position on a sandbank. Therefore we have decided to leave them to sleep for a short while, so that we can reassess the situation when dawn breaks."

The next rescue attempt was launched at just after 1pm on Tuesday when SARA II took tea and chocolate bars to the pair, who had been huddled under a sail for warmth. The plan was to take off the two exhausted men before the incoming tide could roll their exposed small craft. A sailing vessel from Oldbury Pill, HQ for the Thornbury Yacht Club, managed to get a line to the stricken boat.

SARA II then took it under tow to Oldbury.

"We are absolutely exhausted after nearly 24 hours on standby," said a spokesman for SARA at Sharpness.

"The two men are in fairly good shape considering the conditions last night. It turned out to be a far more dangerous exercise than we first realised. At least everyone is safe now."