UNION chiefs fear a new generation of children could be bringing potentially-dangerous laser pens into schools.

It comes after a teacher was injured by a small, hand-held laser pointer in the classroom.

The Darlington teacher, who has not been named but who works at Longfield Comprehensive School, suffered a damaged retina after the laser was shone in his eye while he was teaching last week.

The two children involved were initially suspended but have now returned to school after an inquiry revealed it was not malicious.

But the fact that the youngsters had a laser pen has raised fears that there could be a new rash of incidents in which the potentially dangerous devices are brought into schools.

Martin Fisher, the National Union of Teachers' principal officer in the North-East, said: "We are concerned about any dangerous implement which are brought into schools and result in injury to teachers or pupils.

"It was a big issue a couple of years ago and we did a lot of work to raise awareness of these pens.

"It may be now that a new generation of schoolchildren have discovered these pens, with the ones who used to have them now being a little older and wiser.

"We hope this latest incident was isolated but this could be a time for schools to ensure pupils are given a firm reminder about the dangers of these things."

There were a spate of incidents involving the laser pens three years ago, with attacks on drivers and the police becoming quite common.

Although the pens are not illegal themselves, the Government encourage local authorities to enforce stringent safety rules regarding the devices to make sure that new and more powerful lasers do not fall into the public's hands.

A spokesman for Darlington Borough Council confirmed there was an incident at Longfield School last week, but declined to name the teacher involved.

"A small laser pen was brought into the school but the incident was not malicious," he said.