This shocking CCTV footage released shows laughing yobs hurling rocks at passing vehicles as they speed beneath a motorway bridge.
At least eight drivers have been struck on the M1 in Luton, Beds., including an ambulance which had its windscreen shattered by a brick as it rushed a patient to hospital.
Another three lorry drivers were left with eye injuries after being showered with broken glass during the mindless attacks from several footbridges in the last month.
Bedfordshire Police have now released CCTV footage which caught a gang of hooded teens aged 13-15 pelting rocks at the 70mph carriageway below before fleeing.
A trucker was injured after shards of windscreen glass hit him in the eyes during the attack near Luton Rugby Club at Slip End Road.
Officers hope the film taken of the bridge at 8.40pm on June 17 will identify the thugs before someone is killed is seriously injured.
PC Charlie Pirie, from Bedfordshire Police said the yobs could cause fatal accidents in the future.
He said: ”It goes without saying how dangerous these incidents are.
”There has been expensive damage caused to the vehicles involved, and three drivers have needed medical treatments for glass fragments in the eye – but fortunately none of the injuries have been serious.
”However, it doesn’t take much to imagine what could have happened if one of these heavy goods vehicle drivers had lost control of his lorry.
”Other road users would have been at extreme risk of being involved in a high speed collision and terrible consequences could have followed.”
Previously, an ambulance from Hemel Hempstead, Herts., was hit by a brick as it travelled between junctions 10 and 11 at Luton, Beds., on the northbound M1 on June 8.
East of England Ambulance service spokesman Gary Sanderson condemned the attack which left the crew badly shaken.
He said: ”First and foremost this is a despicable act to carry out.
”This mindless act could had seriously injured or even killed our crew and the patient and other road users on the motorway.
”Words cannot describe how the crew felt following this incident. The crew, both men, and the patient were very shaken up indeed.”
Anyone with information about the yobs is asked to call PC Pirie direct on 01582 304491