The location of every police car-tracking camera in Britain could be revealed following a landmark legal ruling today.

More than 10,000 covert Automatic Number Plate Recognition cameras  photograph and record the registration numbers of 14 million motorists in the UK every day.

The information is used against a national database to track criminals and has proved vital in tackling criminals.

But police forces across the country could be forced to reveal their locations following a Freedom of Information Act request by a member of the public.  In a test case, Devon and Cornwall Police refused to disclose the data but was overruled by the Information Rights Tribunal.

Police chiefs have vowed to fight the ruling in the Court of Appeal but fear every force in Britain will be forced to comply if they lose the case.

A senior officer with the Devon and Cornwall force said: 'ANPR has been a fantastic weapon in our fight against crime.  It has been a huge success, particularly in taking millions of pounds worth of drugs off the streets.

'If we are forced to reveal their locations, then other forces will have to follow, and that raises serious issues particularly around counter terrorism. Giving away that level of detail is frankly ridiculous. It will put the public at risk.'

The technology was recently used to jail a major drugs gang which had supplied more than a million pounds worth of cocaine.

The smuggling ring, which had members from Devon, Norfolk, London and Romford, only unravelled after one of the gang was 'pinged' by an ANPR camera in 2009 for failing to insure his car.

Courier Christopher Leader was stopped by officers on the M5 in Devon in August 2009, when police found five kilos of cocaine worth £250,000 in his car. 

Steven Mathieson, news editor at Guardian Government Computing, submitted an FoI request to four police forces to release data on the location of the cameras back in July 2009.