Three out of the four victims killed at a French Alpine beauty spot were shot in the middle of the head it was revealed today.
The attack, which left four adults dead and one seven-year-old girl in a coma, was described today by a public prosecutor as an act of “gross savagery”.
A four-year-old girl, also involved in the shooting, was under police protection today after being found alive hiding beneath the legs of her slain mother in the bullet-riddled BMW vehicle targeted by attackers.
The girl, who was unharmed in the shooting, was found by police at around midnight - some eight hours after the attack.
She lay undiscovered as police waited for a forensics team to arrive.
Another woman, believed to be her grandmother, was also in the back of the car.
French authorities today struggled to explain why the four-year-old wasn't discovered earlier.
A man in his 50s, named as Saad Al-Hilli from Claygate, Surrey, was found dead in the front drivers' seat of the vehicle.
Mr Al Hilli, who was born in Baghdad, has lived in Britain for 'at least a decade', French police said.
A second girl - believed to be seven-years-old - was found critically injured on the road near to the vehicle.
A male cyclist, named as Sylvain Mollier, was also found dead close to the car - he had also suffered gunshot wounds.
He is reported to have worked for a firm based some miles away and was identified after his wife - who was concerned that he did not return from his cycle ride - reported him missing to police.
A British cyclist stumbled upon the shocking scene and firstly spotted the seven-year-old lying in the road with horrific injuries.
Prosecutor Eric Maillaud said: “She appeared to have been violently beaten to the head and she had many brain injuries.”
Mr Maillaud said the British cyclist, a former RAF officer, was overtaken earlier by the French bicycle-rider found shot at the scene.
He said the British man told them he came across the “powerful” BMW estate with the engine still running.
“He also saw coming towards the car a young girl who collapsed before him,” he said.
“He quickly came to her and put her in a side position and called the police and ambulance service and everyone came to the scene.”
He said the girl had been repeatedly hit “extremely violently”.
French investigators say they still don't know the reasons for the attack.
Maillaud said: “We discovered a little 4-year-old girl that no one noticed earlier because she wasn't moving. Probably terrified, she was completely immobile among the bodies. She was later examined and she is doing OK.”
Maillaud said as soon as investigators opened the door, the girl emerged, smiled and reached out her arms; she spoke English but couldn't describe what had happened and was taken into police care.
“She is in a hospital but her life is not threatened despite going through a tragedy by losing her family in such atrocious conditions,” he said.
Several rescue workers had all apparently peered inside the car.
Local police have said there had been an attempt to steal two cars around Rousillon, some 50 miles away from the killings, on Wednesday night - but it is as yet unclear whether or not this was connected to the shootings.
Maillaud said the four-year-old girl was “terrorised, immobile, in the midst of the bodies”, when she was found.
He said: “As soon as the first forensics began, we were able to open the vehicle, and it was at that moment we discovered the little girl, around four years old, that nobody had seen, because she hadn't moved, completely in shock and completely frozen.”
Maillaud said that 15 cartridges were found around the car indicating that a “very large number” of shots had been fired. The weapon used is thought to have been an automatic pistol.
The BMW was found yesterday on the outskirts of a forest in a car park in the popular tourist region around Lake Annecy - the second largest lake in France.
French officials said the BMW was registered to a UK national who was staying at a nearby campsite, believed to be Le Solitaire du Lac in the Saint-Jorioz area.
Eric Maillaud said the man checked into the site with two women and two young girls, adding: “The owner of the vehicle was British and he was the person who identified himself to the campsite.
He is presumed to be a victim and was accompanied by two women and two little girls. We can assume it's a family, although it is yet to be proved.
“We have been taking evidence, including DNA, which will be sent to the British authorities for confirmation.”
Doctors now say the seven-year-old girl injured in the shooting is out of danger.
She was taken to nearby Grenoble University Hospital where her condition has reportedly stabilised following emergency surgery.
“We don't know when we will be able to question her and I would imagine she is in a state of shock,” Mr Maillaud said.
Police are as yet unsure whether one or more gunman was involved in the shooting, although one theory is that the shots could have been fired during a bungled car-jacking.
The Foreign Office (FCO) said today that it was in contact with the French authorities and seeking further information.
An FCO spokesman said: “We are aware of the reports of the shooting and we are looking into these urgently.”
He added that British consular staff had arrived in Grenoble this morning.
The Foreign Office said that the British Embassy's deputy head of mission in France was also at the scene of the shooting.
“She is liaising with the local authorities and police to get more information,” a spokesman said.
Didier Berthollet, mayor of Chevaline, said the area did not usually have problems with crime.
“We are most surprised by what happened, it is a very quiet village,” he told BBC News.
“It's very popular for all who want to be in a peaceful area.”
Mr al-Hilli's family were named by neighbours today as wife Iqbal and daughters Zainab, seven, and Zeena, four.
A family friend, who would only give his name as James, said Mr al-Hilli had not mentioned he was going away when the pair last spoke in August.
He said: "It was probably a spur of the moment thought, 'let's go to France'.
"He didn't mention this holiday. He just mentioned he had a sore back and was taking a couple of weeks off work."
Mr al-Hilli, who was born in Iraq, moved to the UK in the 1970s, his friend said.
He worked as a freelance computer-aided design (CAD) engineer and had previously helped with designs for the Airbus A380 aeroplane, he added.
He said that Mr al-Hilli's mother had died about 10 years ago while his father died last year.