UPDATE: The British man shot dead with two members of his family in the French Alps has been named as Saad El Hilli by AFP. The family are believed to be from London.
A four-year-old girl was found alive inside a car containing three victims of a fatal shooting spree in the French Alps that is thought to have involved a British family.
Investigators discovered the unharmed youngster among the dead bodies of a man and two women after being called to the massacre in the Haute-Savoie region.
A seven-year-old girl was discovered lying on the road in a critical condition near the BMW people carrier while a male cyclist, named locally as Sylvain Mollier, suffered gunshot wounds and was found dead close by.
A gendarme stands by the caravan where the slain British family were holidaying in a camp site of Saint Jorioz, near Annecy
French prosecutors said the girl of four was only found when investigators began a forensic examination of the car, with reports suggesting this was eight hours after the initial discovery.
It was also reported that she was speaking English and hiding underneath some of the bodies.
Benoit Vinnemann, who is leading the investigation, told the BBC: "The three bodies found in the car appear to be the father, mother and grandmother.
"It is in any case a family, according to British people at the Saint-Jorioz camping site who reported their disappearance on Wednesday night."
Officers were reportedly given a tip-off about the grisly scene by another cyclist.
An investigator enters the trailer where the slain British family were holidaying
Investigators said no weapon has been found and no arrests have been made. It was also unclear if the shootings had been carried out by one killer or a number of people.
One theory is that shots could have been fired during a bungled armed robbery, with the dead cyclist being a witness to the crime.
Local paper Le Dauphine said cyclist Mollier was a 40-year-old father of three, currently on parental leave, and had gone for an leisurely cycle.
His wife, worried when he did not return from his cycle ride, alerted the authorities, without making a link to the killings.
She went to a local police station with a photograph of her husband. Officers quickly made the link and her husband was identified as the fourth victim.
He found himself in the wrong place at the wrong time, Annecy prosecutor Eric Maillaud said.
The BMW was discovered surrounded by spent bullet cartridges on Wednesday afternoon in a car park on the outskirts of a forest near Lake Annecy, a picturesque region popular with tourists.
Maillaud said 15 cartridges were found around the car and that a "very large number" of shots had been fired.
The firearm used in the spree is thought to be an automatic pistol, he added.
The remote area where the bodies were found near Lake Annecy, France
French officials confirmed the British-registered vehicle was owned by a UK national who was staying at a nearby campsite, believed to be in the Saint-Jorioz area.
Mr Maillaud said the man had 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."
Mr Maillaud, who described the scene as being like something seen in a film, said the two dead women were found in the back seat of the car and the dead man was discovered in the front.
The prosecutor added: "At the beginning of the investigation when the investigators got into the car they discovered a little (four-year-old) girl, who was frozen still and uninjured."
"She could not tell the difference between the good guys and bad guys. She spontaneously began to smile and speak in English when the policeman took her in his arms and pulled her out of the car."
He added: "She had heard the noises, the cries but she couldn't say more, she is only four years old."
Mr Maillaud said the critically injured seven-year-old was taken to the nearby Grenoble University Hospital where her condition had been stabilised following emergency surgery.
Doctors have now said she is now out of danger, he added.
"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.
French gendarmes stand guard near vehicles where a British family stayed prior to be found shot dead
A news website in France said investigators had begun inspecting a caravan used by the family at the campsite Le Solitaire du Lac, at Saint-Jorioz.
One woman at the campsite 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 Foreign Office said it was in close contact with the French authorities and seeking further information.
A 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 were on the scene to liaise with French authorities.
Some 60 police officers are at the scene, which has been closed off, and a search being conducted of the nearby forest for the perpetrator or perpetrators.
Specialist investigators from the National Gendarmerie's Criminal Research Institute were sent to the area, near the village of Chevaline, from Paris. Forensic scientists have also been working at the crime scene and a police helicopter was seen overhead.
The website of local newspaper Le Dauphine Libere said the passing cyclist who found the bodies was in a state of shock and has been speaking to police.
According to the official website of the lake, the area is known as the "little Venice of the Alps" and is a centre for paragliding, swimming and watersports.
Many hotels, guest houses and campsites are advertised in the area and it is also said to be popular with hikers, cyclists and mountain bikers and, in winter, snowsports.
A rescue vehicle arrives at the scene where four were killed close to a British-registered car in the Alpine village of Chevaline
The closest French city is Lyon, which is over 100 miles away, while the capital, Paris, is about 350 miles from Chevaline. Geneva, in Switzerland, is around an hour's drive.
Local journalist Leila Lamnaouer told Sky News it is a "very quiet place" where a lot of people go on holiday.
The shooting appears to have been one of the only major incidents reported in the area this year.
Chevaline is about 50 miles from Mont Maudit in the Mont Blanc range near Chamonix, where nine climbers were killed in an avalanche in July.