Yobs who hurled a rock at a train as it sped under a bridge endangering the lives of its driver and passengers are being hunted by police as a new push to reduce railway vandalism comes into force.

The vandals launched their missile as the train passed under a bridge near Apperley Road, Thackley, seriously damaging its pantograph - the arm that links the train to the electric overhead cables.

And the attack is being cited by police officers and Railtrack officials as an example of why they have launched a Track Off campaign, a bid to quash vandalism and trespassing on the lines launched yesterday.

Sergeant Michael Jackson, from the Bradford branch of the British Transport Police, said: "The train which was attacked suffered damage, but the main worry is the people who did this and those inside who could have been seriously hurt.

"There has been an increase on railway damage and vandalism in the area recently. The danger should be obvious to everyone, people can be killed."

Powerful video footage showing the last moments of a child's life and a series of emotive posters front Track Off. Last year, 122 people died on railway lines nationally.

Railtrack's north eastern region, covering Bradford, was the target of 991 reported trespasses and 1,501 acts of vandalism, with Yorkshire one of the worst counties in the country.

Children in Bradford were yesterday reminded about the consequences of playing on tracks with an educational play called I Dare You, aimed at 11 to 12-year-olds, in Victoria Hall, Victoria Road, Saltaire.

The aim of Track Off is to prevent accidents like one last April when John Walker, 16, from West Royd, Shipley, was blasted by 25,000 volts after falling onto overhead railway cables near Thackley Old Road, Baildon.

Police officers will be visiting schools in the city every week to make pupils aware of the dangers and consequences of playing on railway lines.

Nationally, trespass and vandalism left 149 people with injuries last year, cost the industry £26 million, delayed trains by a total of 11,500 hours and accounted for 56 per cent of all stock damage.

Bill Callaghan, chairman of the Health and Safety Commission, said: "Behind those figures lie stories of personal tragedy, not just for the victims, their friends and family, but for the people who deal with the consequences.

"I am delighted that more than 5,000 schools have agreed to link the campaign to the safety and citizenship parts of the National Curriculum and Railtrack has developed a partnership pack available for them from June."

Anyone with information on the incident at Apperley Road, Thackley, at about 5.30pm on Sunday is asked to call the Transport free and in confidence on 0800 40 50 40.

Several people have been interviewed in connection with an incident at the railway bridge in Apperley Lane, Thackley, and released without charge pending further inquries.

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