Police drivers are being retrained in how to respond to 999 calls following a crash in which five teenagers were killed.

New colour-coded driving permits are being introduced and more than 600 officers will be sent on three-day courses following an independent investigation of police pursuits.

The report was issued after Daniel Carwardine and Danielle Martin, both 16, Kelly Goring, 17, Barrie Mackay, 15, and Lee Morgan, 14, all from St Leonards, drove a stolen car into a lamp post and wall in Battle Road, St Leonards.

A police officer was pursuing the car at the time.

An inquest said the officer was not to blame for the tragedy but recommended the force simplified and clarified its system of who can carry out police chases.

Acting Sergeant Paul Sandeman, 29, was not authorised to engage a vehicle in pursuit but mistakenly believed he was.

Deputy Chief Constable Geoff Williams said: "There are of course lessons we can learn.

"Whilst our existing policy complied fully with national guidance on police pursuits, a revised force policy has now been adopted.

"As a result, we have simplified the levels of police driving permit in Sussex Police and started a programme of additional training."

From now on police drivers' permits will be marked with a traffic-light system. A red code means basic driving authority, so officers can drive cop cars from place to place but not respond to 999 calls or exceed speed limits in any way.

Amber means the officer is allowed to chase cars but not stop them. All officers with this grading have to go through a special 'pursuit training' course which tests their reflexes, teaches them about safe distances and theory such as when it is time to call it a day because the chase has got too dangerous.

It is hoped that around 600 officers will have been put through the course by April 2008. Some of them have been previously involved in chases but will still have to be re-trained in the updated course before they are given the official amber certificate.

Green colour coding reflects 'advanced' driver - the highest grade. Officers with this colour on their driving permit can not only chase suspected offenders but box them in and stop them.

Deputy Chief Constable Williams said: "Police pursuits are a high risk activity. Our responsibility is to ensure that, when drivers seek to avoid arrest by failing to stop when required to do so, the police response does not create an even greater risk to public safety. Any officer undertaking a police pursuit must be properly managed, trained and equipped to do so."