Robbers held an Audi owner and his friend at gunpoint during a test-drive, before stealing the £22,000 car.

The owner and his friend had arranged to meet an unknown buyer at a bus lay-by at Dean Clough, Halifax, where four Asian men were waiting for them on Thursday night.

Two of them insisted on going for a test-drive with the friends, but started driving erratically in Thornton.

When the owner tried to call the police, one of the robbers whipped out a pistol, then ordered the men out of the Audi at Pineberry Inn in Mountain, near Queensbury.

This followed two incidents in which women were either tricked or threatened into leaving their cars. Detective Inspector George Marshall, of Bradford North CID, stressed that, although car-jackings were rare, drivers should be aware of their surroundings and keep their doors locked.

"If you think you are being approached or followed, drive to the nearest police station, sound your horn and flash your lights to get attention.

"The Queensbury case is quite unusual. Thieves have stolen cars while taking test-drives but don't often have the buyer with them.

"This buyer wanted to meet on neutral ground in a place of his choosing. Be wary.

"Try to meet in a public area of your choosing, or at your house where there are more witnesses, in case anything does happen. Try to get a car registration number."

Police are still looking for the stolen black Audi estate, registration X665 FOT. On Friday, June 13 two men threatened a 66-year-old woman who was waiting in her car outside a doctor's surgery in Newton Way, Baildon, at 1.55pm. They ordered her to get out, then drove off with the red Vauxhall Astra K225 JUB.

Last Monday, a woman was sitting in her green Vauxhall Astra in the car park of the Farm Store in Thornton, also on the Brighouse and Denholme Road.

At 5.30pm, the driver of the stolen red Astra claimed to have bumped her car and when she had a look, he drove off in her green car, T230 KCP, leaving the red one behind.

Anyone with information about the robberies should contact police on (01274) 376259.