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YouTube video: Motorway missiles can cause severe damage
Kent drivers are being urged to help stop thugs throwing rocks and stones at cars by reporting them.
Around one in five (19 per cent) of motorists in Kent say they've been hit by thrown missiles while driving and nearly 80 per cent of drivers in the county say they've seen someone throwing objects at cars - but hardly anyone who has been affected has contacted the police, according to research by windscreen fitters Autoglass.
There have even been incidents nationally where people have been killed by rocks and stones hitting their cars.
Adrian Walsh from the campaign group RoadSafe is urging motorists across the county to report all incidents to the police.
He said: "At 60 mph a brick will fracture a windscreen and shower glass all over the driver - but at 70 mph it would go straight through and could hit the driver and cause severe damage.
"People have died as a result of this, one person sadly had a heart attack following it.
"The message is for parents to draw this to their children's attention, for schools to cover it in their road safety syllabus and most importantly for people to report incidents to the police when and where they see them."