French investigators in Nantes have ended their probe into the sinking of the French trawler Bugaled Briezh off the Lizard almost ten years ago with the loss of five lives.

Christian Bergot, a lawyer for many of the families involved, said his clients had been notified of the end of the investigation, but that he intended to request further inquiries into whether a US submarine might have been involved.

The Bugaled Breizh sank on January 15 2004 while fishing. Initially the French authorities said that the vessel had snagged its trawl wires in the seabed and capsized.

Subsequently, the blame was targeted towards a NATO submarine with Britain’s HMS Turbulent in the frame for the sinking.

French experts said that HMS Turbulent was not to blame – nor any other submarine. However, now Mr Begot is pursuing whether or not a United States nuclear submarine was in the area at the time of the sinking.

Dominique Tricaud, another lawyer for the plaintiffs, said he would also be requesting the investigation be re-opened into the Turbulent’s possible involvement, denouncing what he called “ten years of government lies and judicial cowardice” in the case.

The wreck of the French trawler was eventually raised and brought into Falmouth before being shipped on a barge to France.