The families of five French fishermen who died off the Cornish coast say the investigating authorities are dragging their feet.
Relatives of the dead fishermen want the Bugaled Breizh salvaged
The Bugaled Breizh sank in January, but French prosecutors refuse to say if it will be raised from the sea bed.
Investigators claim the boat was rammed by a large vessel before it went down.
The chief suspect is a Philippines-registered bulk carrier the "Seattle Trader" and paint debris from her bow is being analysed.
The Bugaled Breizh, which sailed from its home port of Loctudy in Brittany, sank off Lizard Point on 15 January.
It was thought initially that bad weather was to blame for the tragedy.
But French prosecutor Roland Eisch said photographs of the trawler suggested it went down after a "very violent" collision.
The vessel sank in an area where naval exercises are carried out, but all the warships in the area had been accounted for and could not have been responsible.
Relatives of the dead fishermen were among a crowd of about 1,500 people who marched in silence through the town of Quimper to the courthouse where Mr Eisch is based.
The families want the trawler salvaged to gather more evidence and look for the remains of three of the crew who have never been found.