Sergeant Alun Williams at one of the check points in Swansea

A hi-tech police operation aimed at catching drug dealers, burglars and other criminals is taking place across south Wales.

Police vans and cars equipped with a computer system that instantly identifies vehicles wanted by officers or the DVLA have been deployed at road checks.

Operation Arrow Head is the biggest initiative of its kind to be carried out by the South Wales force and will continue until 2000GMT on Thursday.

The licence plate of every vehicle that passes the checks is electronically swept to see if it is one of 10m that is either untaxed, unregistered or has been flagged up by police intelligence.

Unless they are on the data base they will not be stopped Chief Inspector Adrian Gough

Scores of vehicles that are on the wanted list have been pulled over and the drivers questioned by officers on the road side.

Pursuit cars and the force helicopter are on standby should any motorist refuse to stop.

Interception team

Sergeant Alun Williams said: "We are targeting criminals that are using the road.

"Any vehicle passing the system has its number plate read.

Officers monitor the ANPR system in the back of a police van

"If it triggers an alarm on the system then the details are passed on to the interception team.

"Our focus is on burglary, auto crime, drug dealing, disqualified drivers and vehicles that may have been involved in a robbery."

Of the 10m vehicles on the data base, six million have no tax, two million are unregistered and the rest are either stolen or are believed to have been involved in crime.

Details of anyone caught for motoring offences are to be passed on to the DVLA while those involved in criminal activity are being dealt with by officers.

Seven police vehicles are equipped with the Automatic Number Plate Recognition (ANPR) system and are being used at various check points throughout the day.

Altered plates

Chief Inspector Adrian Gough said it allowed officers to target identified vehicles without having to stop law abiding members of the public.

"Unless they are on the data base they will not be stopped," he said.

Police have been trialling the system since June and it has already resulted in 366 arrests.

Sergeant Williams said more and more vehicles would be equipped with ANPR in the future.

"We have already encountered people trying to change or alter their number plates," he said.

"But the system is getting better all the time and technology is increasing so basically no vehicle will get passed us without its number plate being read."