Bad weather conditions had seen the operation to find Maldwyn Jones, 60, called off.

However the Underwater Search Team, who are based in Runcorn, Cheshire, are currently searching the area around Trefor off the Gwynedd coast.

Mr Jones was last been seen at 3.40pm on Monday, putting out lobster pots 10 miles south west off the coast of Porth Dinllaen.

Reported to be a poor or non-swimmer, it was also confirmed by Holyhead Coastguard that Mr Jones was not wearing a life jacket.

The alarm was raised on Monday evening, after Mr Jones' vessel, named the Provider, was discovered unmanned and circling by the crew of another fishing boat.

Subsequently a large search operation got underway, involving a helicopter from North Wales Police, a helicopter from RAF Valley, two lifeboats and other fishermen who work in the area, a spokesman for the Maritime and Coastguard Agency (MCA) said.

Glyn Roberts, chairman of the Llyn Fisherman's Association, confirmed that Mr Roberts, originally from Aberdaron, had been working in the industry for three years.

Association development officer Mike Parry explained that over 90 per cent of fishermen in Wales worked alone, and most had had "narrow escapes".

He added: "Many fishermen in the country do their work single handed, so here at the Association we provide training such as fire fighting and sea survival."

Prospective councillor for Nefyn, E Meinir Jones said: "This must be an awful time for the family and I am very sorry to hear the news.

"Everyone knows that fishing can be a dangerous profession but this is a very sad event, and I feel for the family and their loss."