Three of the four people shot dead when a gunman opened fire on a British family in the French Alps were hit in the middle of the head, it was revealed today
Public prosecutor Eric Maillaud described the attack, which left the driver, two women and a passing cyclist dead, as an act of "gross savagery".
A four-year-old girl was found alive underneath the bodies of her family around eight hours after the massacre.
A seven-year-old girl, thought to be her sister, was found violently beaten and is in a coma, fighting for her life.
The four-year-old lay undiscovered as police waited for forensic experts to arrive at the scene from Paris. She was found "terrorised, motionless, in the midst of the bodies" after fellow campers at a nearby site told officers the family had two children, Mr Maillaud said.
He defended the delay in finding her as he revealed she was receiving psychiatric treatment.
A man and two women - believed to be the girls' mother, father and an older relative - were in the British-registered BMW, which was riddled with bullets.
The man was named by French media as Saad al-Hilli, from Claygate, near Esher in Surrey.
Mr al-Hilli was behind the wheel at the time of the attack.
Mr Maillaud refused to confirm his name but revealed that he was 50 years old, was originally from Iraq and held British citizenship.
A British cyclist, a former member of the RAF, who stumbled upon the shocking scene and spotted the seven-year-old lying in the road, placed her in the recovery position.
Speaking at a press conference today he was praised by Mr Maillaud, who said the four-year-old was in a traumatised condition.
"Can you imagine the state of the young girl, four years old, has spent eight hours under a body that was not moving..."
Police said the motive for the attack remained a mystery but revealed there were signs of a vehicle braking at the scene.
Mr Maillaud also revealed that Swedish and Iraqi passports had been recovered along with the driver's British passport.
Mr Maillaud said the British cyclist 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".
The British cyclist then went the vehicle and found the French victim by its side. He broke a window and turned the car engine off and found the other three bodies in the car.
"We are talking about particularly horrific and alarming deaths," he added.
The media gathered outside Mr al-Hilli's home in Claygate, Surrey this afternoon.
Two plain-clothed police officers stood outside the two-storey detached house before three uniformed officers arrived.
Two of the officers entered a gate at the side of the property.
Neighbour Jason Kosbab, who said he did not know Mr al-Hilli's family, said: "Claygate is a very close knit village. This is certainly going to bring everybody together."
Mr al-Hilli and his family had been holidaying in a caravan at the Le Solitaire du Lac campsite in nearby Saint-Jorioz.
Their BMW was discovered surrounded by spent bullet cartridges in a car park near footpaths on the outskirts of a forest near Lake Annecy, a picturesque region popular with tourists.
The cyclist who reported the shooting is thought to be a retired man who was familiar with the area and was a regular visitor.
Speaking earlier Mr Maillaud described the scene as being like something from a film and said 15 cartridges were found around the BMW and a "very large number" of shots had been fired.
The firearm used is believed to be an automatic pistol.
The two dead women were found in the back seat of the car along with a number of bags.
The seven-year-old was taken to the nearby Grenoble University Hospital where her condition had 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.
Investigators said no weapon had been found and no arrests had been made.
It was also unclear if the shootings were carried out by one killer or a number of people.
Mr Maillaud said: "We don't know who could have done this. We have no idea."
One theory is that shots could have been fired during a bungled armed robbery, with the dead cyclist - named as Sylvain Mollier - being a witness to the crime.
He worked for a firm based some miles away and was identified after his wife became worried when he did not return from a bike ride.
She went to a local police station with a photograph of her husband and officers established he was the fourth victim.
Mr Maillaud said he found himself in the wrong place at the wrong time.
Investigators were today inspecting a caravan used by the family at the campsite.
One woman said: "I saw the two women yesterday with the two little girls collecting apples.
"Everything seemed normal, but I didn't know them. It was the first year that they had been seen here. It is terrible. The atmosphere is heavy, nobody is speaking."
The British Foreign Office said the British Embassy's deputy head of mission in France was at the scene of the shooting.
"She is liaising with the local authorities and police to get more information," a spokesman said.