A lorry driver had a “lucky escape” after a sack was thrown from a motorway bridge smashing through his windscreen.
Police said the driver, who was on the M5 near Tewkesbury, kept control of the HGV but was “shocked” by the incident.
Three teenagers, aged 15 to 16, were seen standing on the bridge before one of them threw the sack at the lorry.
Officers have appealed for witnesses to the incident, which happened shortly before 23:00 GMT on 31 October close to junction 9 of the M5.
PC Tim Griffiths, said: “I cannot stress in the most serious terms how dangerous it is to do such a stupid thing.
“The lorry driver could have been seriously hurt or even killed. If he had been rendered unconscious or had lost control of his lorry then we could easily have been dealing with serious injuries or fatalities.”