Media playback is unsupported on your device Media caption Brett Martin told the BBC that the scene of the shootings "was like something out of a Hollywood movie"

The ex-RAF pilot who found a British family murdered in the French Alps feared "some nutter" with a gun could still be nearby to shoot him next.

Brett Martin, from East Sussex, helped Zainab al-Hilli, seven, after the attack which claimed the lives of her parents, grandmother and a local man.

He told the BBC he made the difficult decision to leave her bleeding on the ground while he went to seek help.

Meanwhile, a French prosecutor has said the motive has its "origins" in the UK.

Eric Maillaud was speaking outside Woking police station in Surrey after arriving with the French judge leading the inquiry.

French and British police are continuing to search the Claygate, Surrey, home of Saad al-Hilli, 50, who was shot with his dentist wife Iqbal, 47, mother-in-law, 74, and passing cyclist Sylvain Mollier, 45, in Chevaline, close to the tourist destination of Lake Annecy.

Zainab and her four-year-old sister Zeena both survived the attack on 5 September during their camping holiday.

Mr Martin said he initially believed there had been a car accident after coming across the scene while cycling in the forest area.

Police protection

He told the BBC the car's engine was running when he arrived and he had to break a window on the vehicle to switch it off.

It became quite obvious, taking stock, that it was a gun crime Brett Martin, Witness

"At first I thought there's been a terrible accident between a cyclist and a car because there was a cyclist on the ground, more or less in front of the car, but there were things that didn't quite match because the cyclist's bike wasn't beside him, so as the minutes went on I started to change my opinion," he said.

He saw three bodies in the car, and once he realised a crime had taken place, he was worried who might still be around.

"There was a lot of blood and heads with bullet holes in them," he said.

"I've never seen people who've been shot before... but it seemed to me just like a Hollywood scene, and if someone had said 'cut' and everybody got up and walked away, that would have been it, but unfortunately it was real life.

"I then started scanning the woods to see if there was some nutter or who knows what with a gun and I was going to be the next person shot."

He moved Zainab, who collapsed on the ground after he found her "stumbling" away from the car in case it began moving but said he faced a "dilemma" when he decided to seek help after finding his mobile phone had no reception.

He said he felt Zainab's injuries would have worsened - "perhaps killed her" - if he had carried her with him.

Image caption The French prosecutor briefed reporters after meeting police in the UK

Mr Martin added that he has since travelled back to the location of the shooting under armed police protection to give further details to French officers.

French police have spoken briefly to Zainab, who remains in hospital in France after being shot in the shoulder and hit around the head. But they are still waiting to question her fully.

Zeena, who lay undiscovered in the car for eight hours, has returned to the UK and is under the care of social services.

On Wednesday, Mr Maillaud said 40 French police officers were working on the investigation and probing Mr al-Hilli's work as an engineer, his family connections and possible links within Iraq.

'Productive meeting'

After talks with Surrey Police officers, the prosecutor told reporters: "Without any doubt... the reasons and causes have their origins in this country."

Surrey Police said they had held an "extremely productive" meeting with French and British officials involved in the investigation.

A spokesman said: "The meeting built on the already established strong working relationships between all parties involved. The UK and French authorities are extremely pleased with the progress which has been made."

The BBC's Christian Fraser, in Annecy, said the purpose of the visit was partly to "iron out" differences between the forces. On Wednesday Mr Maillaud said the language barrier between French and British officers had been slowing inquiries down.

Meanwhile, the family's BMW car has been sent to Paris for forensic tests and inquiries are also said to be taking place in Sweden, where Mr al-Hilli's mother-in-law had a property.