There has been a disturbing increase in recent years in the number of incidents involving stones and other missiles being thrown at cars, or dropped on to them from bridges. There have been similar attacks on trains, which recently led to special police patrols being set up along the Aire Valley line.

The latest series of incidents has been making life difficult and dangerous for motorists on the Otley by-pass. In one, a woman driver narrowly escaped serious injury and had expensive damage caused to her car when large stones were thrown off the footbridge that crosses the road. On another occasion a man driving towards Otley from Bradford had a traffic cone hurled at his car in the same spot.

That attack caused £350-worth of damage. However, it and the other incidents could just as easily have cost someone their life.

The police suspect that local youths are responsible. They are playing a very foolish and dangerous game on the edge of a comfortable Wharfedale market town. They can't blame the frustrations of inner-city poverty for their actions, or the bleakness of life on a grim estate. It is plain stupidity and possibly even malice which causes youngsters like these to put other people's lives at risk.

The police say that despite extra patrols it is difficult to catch the culprits because the incidents are well spaced out. In that case it is up to members of the public to be extra vigilant and report anything they see. These yobs need to be caught and dealt with in a way which makes it clear that such behaviour simply will not be tolerated.