A diver died and his brother is receiving emergency treatment after they suffered the bends while exploring a Sussex shipwreck.

The incident happened at 3.30pm yesterday at the site of a sunken boat, 12 miles off the coast at Shoreham power station.

Two men were airlifted from the Brighton-based boat Girl Gray, which was being used by a party of divers to investigate the shipwreck.

The brothers had dived together and were 'buddying' for each other but surfaced too quickly.

One died soon after. He was 40 years old, from Copthorne near Crawley. He has yet to be formally identified.

His 37-year-old brother is from Surrey and was this morning at the county's Whipps Cross Hospital, where he was taken by the Coastguard helicopter.

He has spent several hours in a recompression chamber. His condition is said to be stable.

Both brothers were qualified and experienced divers.

Mike Snelling, director of Southern Marine Services, which owns the Girl Gray, said: "The Girl Gray transported divers both days of the weekend. A diver who had left the boat on Sunday suffered an accident.

"He was evacuated by helicopter with his colleague. One man died and the other is being recompressed. The last information I have is that he is in a critical condition."

The Southern Marine Services web site states: "We operate one of the UK's finest small work boats which can also take you out for sea angling, diving, or for an enjoyable party trip from Brighton Marina.

"Girl Gray has comfort, speed, functionality and, above all, safety."

A spokesman for the Solent Coastguard said the two men were picked up by a rescue helicopter.

One was dead on arrival at hospital in Brighton and the other was taken to a recompression unit in London.

A spokeswoman for Sussex Police said: "There was a tragic accident yesterday afternoon as a party was diving at a shipwreck.

"Two men buddying appeared to surface too quickly and suffered from the bends. One died and the other is in a critical condition."

The incident has been referred to the Health and Safety Executive. Brighton and Hove's coroner has been informed.