Delivery vans have become the hottest targets for thieves as the number of vans reported stolen in the city in the first nine months of this year reached 334. This compares with 300 stolen in the whole of last year.

There were 254 in 2005.

The number accounts for 30 per cent of the total number of stolen vehicles in the city.

This goes against the trend of a decreasing number of stolen vehicles of all kinds.

The number of stolen vehicles dropped 22 per cent to 1,084 in the first nine months of this year, down from 1,381 in the same period last year.

Police said there had been a downward trend in the number of stolen vehicles in the city, from 2,804 in 2000 to 1,774 last year.

Officers say thieves usually target late-model goods vans worth about HK$200,000.

Some of the vehicles have their owners' business contact number painted on them, allowing thieves to phone them and demand money for their return.

'We believe goods vans have become the targets for thieves because the vans are used to do business and their owners will suffer losses every day without them,' a police source said.

The source said thieves would usually demanded between HK$20,000 and HK$30,000. Once they received the money, they abandoned the vehicle in a street near the owners' address.

'Our experiences show the owner will not reveal to police that he paid the money,' another source said.

'It's possible that they could have been warned by thieves that their move could lead to criminal liability for assisting offenders to commit a crime.'

The source said thieves would set alight the vehicles if owners refused to pay.

'Otherwise, they might smuggle the stolen vehicles into other Asian countries or dismantle them to sell the parts on the underground market in Hong Kong,' the source said.

Investigators believe more than one gang is involved.

On October 3, a goods van stolen in Ngau Tau Kok was abandoned and torched in Pat Heung after its owner received a phone call from a thief but refused to pay up.

Ip Moon-lam, chairman of the Hong Kong Union of Light Van Employees, said he was not surprised that owners chose to pay to get their vans back.

'They think it is a quicker way to get back their vehicles and resume their delivery business,' he said.

'In addition, they will not have to face hefty car insurance charges next year.'

A police spokesman said that to protect their vehicles, owners should use a gearbox or pedal lock or install an alarm or a hi-tech vehicle tracking system.

But Mr Ip said: 'They're professional thieves. They can unlock the vehicle's door with a metal-made ruler and easily unlock a gearbox or pedal lock with other handy tools.'

According to police, thieves have mainly targeted luxury cars in the past and owners had to pay up to HK$50,000 to get them back.