DETECTIVES hunting a French doctor suspected of killing his wife and two children joined forces with Scottish police yesterday in the latest attempt at making a breakthrough in the four-year-old investigation.

A member of the public claimed to have seen Yves Godard in Lewis in 1999, just months after he allegedly killed Marie-France Legraverend, his wife, in France. Her body has never been found but police suspect it was dumped in the English Channel.

At around the same time, Dr Godard disappeared with his son, Marius, four, and daughter, Camille, six, on a yacht at the French port of St Malo. Camille's skull was recovered from the sea in June 2000 and French police have been treating her death as suspicious. Marius is still missing.

Two senior officers from the Gendarmerie Nationale yesterday returned to the Western Isles for the second time in the investigation in the hope of establishing firm evidence that Dr Godard travelled to the area.

Their first visit, immediately after the tip-off in 1999, ended in a bitter dispute with their Scottish counterparts, who they accused of a lack of zeal.

The Northern Constabulary claimed the French detectives had failed to get the necessary Crown Office clearance for their investigations. It has taken four years for French police to return to the Western Isles, which a Northern Constabulary spokesman said yesterday was due to ''international

protocols''.

At a joint press conference in Stornoway, the two forces called for anyone who might have seen the doctor in the Western Isles four years ago to contact them.

Detective Inspector Gordon Greenlees, who is helping the French investigation team, said: ''The essence of the French Gendarmerie investigations in the Western Isles is to establish whether Dr Yves Godard and his children, Camille and Marius, were in the islands during October 1999. ''On behalf of the French officers, I would appeal to anyone who may recall seeing Yves Godard and his two children in the Western Isles in October 1999 to contact Stornoway police station.

''In particular, I would appeal to hotel and guest house proprietors, taxi drivers, employees of harbours, airports, car rental firms, or the retail trade to examine the photographs of Yves Godard and his children and to contact Stornoway police station if they recall seeing any of them.''

The hunt for Dr Godard began on September 1, 1999, when he chartered a Sun Odyssey 30 sailing yacht in

St Malo, taking his two children with him.