The long arm of the law has hopped aboard a very small train to deter troublemakers in Romney Marsh.

Burly policemen have been riding the 15in gauge Romney, Hythe and Dymchurch Railway to stop children going off the rails.

One officer sits on the train and alerts two others waiting in a car if they see anything suspicious.

Kent Police say they were prompted to try the idea last month by the rise in graffiti and anti-social behaviour in the school holidays.

And the tactic has paid off, with four youths who were causing trouble by throwing a ball over the trains having their details taken.

Acting Sgt Will Glennie said: "Neighbourhood officers and police community support officers are deployed to the area on days which have been identified as most problematic.

"One officer is on the train, and two officers are patrolling in a vehicle.

“They are called up by the officer on the train should he witness youths committing criminal damage as he passes through.

"He is also able to deal with any instances of anti-social behaviour which may take place on the train."

The scheme has been praised by town councillors in New Romney, including Cllr Jane Hiscock.

She said: "Every year a lot of the children were playing chicken on the tracks.

"But with the police on hand to warn them about the dangers, it seems we've got rid of a lot of the problem."

The steam line is the smallest public railway in Britain.

General manager Danny Martin said: "Police contacted us because we had a few incidents earlier in the year. They use the passenger cars and get on with all the staff.

"It's really worked - the number of incidents has fallen by 60 per cent."

A police spokesman said: "The initiative is in direct response to previous years where there have been reports of trouble.

"The aim is to identify offenders, prevent damage and tackle instances of anti-social behaviour."