Car drivers in South Africa are being offered a new method of preventing hijacking.

The BBC's Jeremy Vine witnesses a demonstration of the "blaster"

A blaster, flame-thrower operated by a foot pedal inside the car, blasts a jet of fire at a would-be hijacker.

A person confronted by an armed hijacker simply presses a pedal and the "blaster" ignites gas that shoots from the under-side of the car.

Doctors say the device is lethal - but the police have confirmed it is perfectly legal.

"Drivers - put up your hands and step on the gas"

Johannesburg seems to fill car drivers with fear. In the province which includes the city, there were 4,000 car hijacks between January and June this year.

People pull up at traffic lights, they stop their car and then someone comes up to the window with a gun and tells them to get out.

Charles Fourie, who invented the blaster, says drivers should put their hands up and then step on the gas.

"This is a case of opting for the lesser of two evils," Mr Fourie said.

"Either you get shot, your wife is raped, your child is murdered - against him getting burned."

No legal problems

Police say they cannot see any legal problems with the blaster - so long as the right people are blasted.

The blaster: Doctors are appalled

But Dr Kenneth Boffard, a surgeon who runs a trauma unit, said he is extremely concerned.

"I don't think the average person on the street has any concept of the appalling damage that burns cause," Dr Boffard said.

"The result of that is permanent, extensive and disfiguring."

"Innocent people are going to get caught.

" That's unacceptable."