Transport police have highlighted the lethal dangers of York's train lines after two teenagers were caught trespassing at a rail bridge on the outskirts of the city.

The 14-year-olds were cautioned by British Transport Police (BTP) officers after being found on tracks near Skelton railway bridge, a notorious trouble spot close to the A19.

A member of the public reported that children as young as ten had been seen under the bridge, climbing up on to the rails and even jumping from it into the River Ouse. Officers warn that youngsters playing on the narrow bridge are putting their lives at risk from high-speed trains, electrified lines and hidden dangers lurking in the shallow water beneath.

PC Kevin Andrews, of York BTP, said his unit would be increasing patrols on both the Skelton and Upper Poppleton sides of the river.

He said: "Railway lines are not a playground and these children should know better. We are also appealing to parents to make sure they know where their children are this summer."

The warning came as BTP Chief Inspector Danny Snee met the Lord Mayor of York, councillor Chas Hall, at York Railway Station to discuss a national railway crime initiative. Every school in North Yorkshire has been targeted this week by the rail industry in a drive to cut incidents of trespass, vandalism and objects left on tracks. Chief Insp Snee said: "We've got patrols out every day and every day we will catch somebody trespassing. Parents would not let their children wander across the M1 motorway and railway tracks are equally as dangerous."

Parish councillor Susan Robinson said she and other councillors would mount patrols in the Skelton bridge area.

She said: "It's extremely dangerous because the bridge is narrow and there's no real walking space up there. The river isn't very deep at all if anyone is jumping into the water. We're coming up to the summer holiday and we really don't want children playing down their, putting themselves, and others, in danger."

A spokeswoman for Network Rail, which operates the tracks, said people often forgot about hidden dangers such as soft ballast and moving points that could trap a leg or foot.

She said: "It may seem like an act of childish fun or a bit of a laugh between friends, but it can cost a life. Anybody who commits an act of trespass or malicious crime on the railway not only risks their life, but the lives of others."

Last year, three York teenagers admitted trespassing on Skelton railway sidings. Two received fines and the third was given a referral order and £55 costs. One of the group told police he had gone to a hut close to the railway track to "chill out" and had not realised he was acting illegally.

Updated: 10:52 Wednesday, June 18, 2003