GREATER Manchester Police (GMP) is warning young people to think twice about their actions after a rise in incidents of items such as bricks and rocks thrown onto the M60.
The force is seeing a number of these incidents result in damage to vehicles, including one where a car's windscreen was smashed when it was at full speed on the motorway.
Superintendent Julie Ellison, of GMP's Specialist Operation Team, warned these reckless acts might soon result in loss of life.
She also appealed to parents to take responsibility for their children's actions and movements as the school holidays approach.
Superintendent Ellison said: "It goes without saying that behaviour such as this is reckless and it puts multiple lives in danger.
"Not only can it cause serious damage to vehicles, but even more worryingly, it can result in serious injury to those travelling in the vehicle and potentially cause a devastating collision.
"We already have officers patrolling known locations, who will not hesitate to take action against perpetrators, to ensure that those travelling can do so safely, so I would encourage young people to think about the consequences of a spilt second silly decision or an attempt to show off, that it can have serious consequences for them and others.
"In addition to this, I would also like to appeal to parents. As we move into warmer weather and school holidays approach, I ask that you check what your children are up to, and where they are going, as well as speaking with them about the importance of making safe and responsible decisions."
Alan Shepherd, North West regional director for National Highways, echoed the superintendent's message.
He said: "When the evenings get lighter, we do get an increase of incidents involving children and teenagers playing near motorways and on motorway bridges.
"Staff at our regional operations centre near Warrington work closely with the police to monitor our motorways around the clock, with an extensive network of CCTV cameras recording at locations all the time.
"If the threat of prosecution is not warning enough, we would ask parents to have a conversation with youngsters about the potentially tragic consequences of stone-throwing and of playing near the motorway."
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