British Transport Police and Network Rail's campaign "You vs Train" warns "Everyone loses when you step on the track", and follows serious injuries caused to Tom Hubbard, a young boy, in 2014.
They are urging people to "consider the serious and devastating consequences, for them and their loved ones, when they ignore warnings and go onto the railway."
There are particular dangers surrounding school holidays, when more children risk their lives by trespassing onto railways.
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