French police believe al-Hilli murderer could be crazed serial killer with a hatred of tourists

Saad al-Hilli, the Iraqi-born father who was shot dead in the massacre in the French Alps

Police officers investigating the horrific massacre of a British family in the French alps believe they were murdered by a crazed serial killer with a hatred of tourists.

The Sun newspaper claims that police have linked the murders of Saad al-Hilli, wife Iqbal and mum-in-law Suhaila Iqbal with another tourist killing.

The motive for the murders, which happened while the family were on a camping holiday, has so far been a mystery to French police.

However, detectives now appear to have linked the murders with that of Xavier Baligant, 29, who was shot four times at a rest area off the A13 near Nancy in July. His sons, Dylan, five, and Jordan, seven, were in the car at the time, and were left unharmed.

Police believe the gun used in the attack was very similiar to that used in the killing of Saad al-Hilli and his familiy members.

The weapon is thought to be a collectors' item, and was used by the Swiss army before the First World War.

Mr al-Hilli, 50, his 47-year-old wife Iqbal, his 74-year-old mother-in-law and French cyclist Mr Mollier, 45, were killed by a lone gunman at an isolated lay-by close to the village of Chevaline, near Lake Annecy.

Initially it was suggested the killings were a professional hit, and that more than one gunman may have been involved.

Mr al-Hilli's daughters Zainab and Zeena survived the shooting in September.

Police were unable to find any DNA at the scene, but shell-casing identifying the weapon as an antique Luger were found.

Earlier this week French police indicated all lines of inquiry remained open.

French investigator Eric Maillaud said: "Without doubt we are looking for someone who has killed before, someone who puts no value on human life.'