YOUNGSTERS who pelt passing cars with bricks and stones are putting people's lives at risk, claims an accident expert.

Last week two vehicles were 'bombarded' with stones as they passed under Carlisle Bridge in Lancaster, shattering the windscreen of a passing car.

Both drivers were shaken by the incidents and a group of children were spotted running towards Ryelands estate.

A spokesman for the Royal Society for the Prevention of Accidents said the actions of these youngsters were sheer "idiocy."

He said: "We've got to get the message home to these people just how dangerous this type of activity can be.

Even a small object thrown from a height can smash a windscreen and kill the driver or their passengers.

At the very least it cause them to swerve and endanger other cars or pedestrians.

They should also realise that they could be putting in danger someone they know or even a family member."

Both cars were caught in congestion on Thursday afternoon and the first to be hit was a Rover 600, which was struck on the passenger side.

Then a Ford Escort was struck, shattering the windscreen.

Police were informed and a spokesman said that they were investigating and urged anyone with information to come forward.

A spokesman for the AA said this type of incident happened across the country and added: "If motorists see people acting suspiciously on bridges they should note what they look like and contact the police.

Parents should also be aware where their children are at all times."