The British businessman Saad al Hilli, who was killed with members of his family in the French Alps last month, had filed a lawsuit over an alleged forged will, it was reported yesterday.

Mr al Hilli had begun proceedings in an attempt to prove his father's will had been forged, reports say.

Several versions of the will, worth £4 million, were found in the family's caravan near Annecy in south-eastern France, sources said.

Annecy magistrates probing the murders of Mr al Hilli, his wife Iqbal and his mother-in-law Suhaila al Allaf, as well as the shooting of his daughter Zainab, have asked UK authorities which judicial authority the Surrey businessman had turned to.

He was shot dead, along with a French cyclist, Sylvain Mollier, on September 5 in woods south of Annecy. French magistrates are seeking documents Mr al Hilli stored on internet servers around the world.

"Saad had all his life on his laptops, and he stored documents on foreign servers which are all over the world," Eric Maillaud, chief prosecutor in Annecy, said.