A local builder who rescued a 71-year-old man clinging for his life to a marker buoy has brushed off his act of heroism as "just instinct".

Martin Williams, from Haverfordwest, was working at a property on the Promenade, Neyland, on Friday when he was alerted to screams for help coming from the sea.

He got to the door of the property and saw a man clinging to the mooring buoy of a yacht and a dinghy washed up on the beach towards Llanstadwell.

The man had slipped while climbing from the dinghy into the yacht.

He had been in the water for around 25 minutes.

"I'm a boating man; as soon as I came out the door I knew what had happened and what was going on," said the 47-year-old. "I didn't think about it. I just went."

The keen sportsman ran across the mud flats to the boat, rowed it out to deeper water and then started the engine.

He got to the distressed pensioner, whose cries for help were getting fainter.

"I was shouting to him to hang on as I was running across the beach," said Martin. "When I got to him his foot was tangled in the mooring rope."

Martin managed to free the man's foot and drag him into the dinghy before racing back to shore.

Three other Neyland men, Simon Bolton and Ryan and Billy Miller helped get the sodden and cold casualty up the beach and up to the road.

"Hearing someone scream for help like that is one of the most horrible things you can hear," said 35-year-old Simon.

"It was just one of those things where people felt helpless but you had to do something. He was a lucky man that's for sure."

Simon took off his body warmer and put it on the pensioner, while a woman from a nearby house provided blankets and duvets until the emergency services arrived.

Martin then changed out of his wet clothes and went back to his plastering.

"He was very lucky that the water was about 14 degrees, you can survive in that for a pretty decent time," he said.

"If it was at normal November temperature it would have been curtains."

"I just did what I had to do. There was no thought it was total instinct. It was what I hope somebody would do for me if I was ever in that situation."