Police are continuing to question the brother of a British engineer shot dead with his wife and mother-in-law in the French Alps, over the alleged fabrication of his late father's will.
French officials confirmed Zaid Hilli was arrested yesterday on suspicion of conspiracy to commit murder after evidence uncovered by officers suggested he doctored documents to ensure he inherited the estate.
Mr Hilli, 54, has previously denied any feud with his brother over an inheritance. He approached police to deny suggestions of an argument over the will after the dispute between the brothers came to light soon after the murders.
Detectives searched Mr Hilli’s home in Chessington, Surrey, and were later seen leaving the property with a plastic box, a ladder and two bags.
Eric Maillaud, Annecy's Public Prosecutor, said police would now attempt to establish any link between the alleged fraud and the brutal attack which killed Saad and Ikbal Al-Hilli, Mrs Al-Hilli's mother Suhaila al-Allaf, and local cyclist Sylvain Mollier.
Mr Maillaud said: “We know there was a dispute between the two brothers over their father's will.
“There are a certain number of documents that suggest Zaid attempted to fabricate his father's testimony in his favour.
“It looks like he tried to take the fortune for himself. That did not work but we want to ask him questions about it.”
Mr Maillaud said detectives were aware of the allegedly false documents from an early stage in the investigation.
The arrest is the first significant development in the inquiry following the attack that took place a remote mountain road close to Lake Annecy on 5 September 2012.
Saad Al-Hilli from nearby Claygate, his wife Iqbal and her mother Suhaila al-Allaf, who lived in Sweden, were shot dead with a French cyclist, Sylvain Mollier in a remote forest lay-by near the village of Chevaline.
Their daughters survived the shooting. Four-year-old Zeena was discovered hiding under her mother’s body inside the family car, eight hours later. Her sister Zainab, seven, was found with serious head injuries after being shot and beaten. The two children returned to the UK soon after the killings.
Approximately 100 police officers from the UK and France have been tasked with investigating the deaths. Last year French investigators travelled to the UK to search the al-Hilli family home in Claygate, Surrey.
Their inquiry has focused on examining Mr al-Hilli's work, links to his native Iraq and his family.
Ahmed Al-Saffar, the brother of Mrs al-Hilli's dead mother, said both the al-Hilli and Al-Saffar families were heartbroken by the killings in a statement issued after the deaths.
“We hope that those responsible for the deaths of our loved ones are brought swiftly to justice,” the statement read.
One man who lives in a neighbouring flat described Mr Al-Hilli as a “lovely man”.
Philip Davies, who lives in the flat below Mr Al-Hilli, said he had seen police at the address “on various occasions”.
He said of his neighbour: “Nobody really has had anything to do with him. He's been living here about a year or 18 months.”
Detectives investigating the massacre appealed for help in April to trace a vehicle witnessed close to the scene just before the deaths.
Officers said they were looking to speak to the owner of a right-hand drive 4x4 vehicle, possibly a grey, black or dark-coloured BMW X5, which was being driven on the Combre d'Ire Road, Chevaline, at about 3.20pm on 5 September.
The attack came as the Al-Hilli family holidayed at a campsite near Annecy, in south east France.
Surrey Police said a 54-year-old suspect was detained following a pre-planned arrest at an address in Chessington at around 7.30am, and had been taken into police custody to be questioned.
The four bodies were discovered by cyclist Brett Martin who arrived at the scene to find the bodies of Mr Al-Hilli, 50, his 47-year-old dentist wife and her elderly mother in their BMW. He found the al-Hillis' seven-year-old daughter Zainab “stumbling” around, bleeding and “moaning” near the car after being attacked.