RAT poison was laid at a Gwent school after evidence of vermin was found.

The 1,460-pupil Caldicot Comprehensive School confirmed it had called in environmental health experts after rat droppings were found in the premises.

Today, governors and parents said they were "seriously concerned."

The school is split-up into four buildings - Grayhill, Castle, Deepweir and Wentwood. Headteacher John Norwood (pictured) said: "We have had a report that rat droppings have been found in the Grayhill building of the school.

"That has been thoroughly investigated by environmental health officers and they have laid down rat poison as a precautionary measure. All the poison is out of pupils' reach. "Somebody has reported the droppings and we have to investigate - but no-one has seen the Pied Piper.

"We will not close the school until we are advised to so by the local education authority or the environmental health department."

The Argus understands the problem centres on a former toilet-room on Grayhill building's first floor, where it is thought rats climbed up through pipes.

The storeroom has never been used by pupils.

Councillor Mike Smith, chairman of Caldicot school's governing body, said: "It is concerning that the presence of rats has been confirmed at the school because no-one wants a school infested with rats.

"It is not uncommon for rats to congregate where there is food but I would hope that environmental health officers will help us eradicate the problem.

"If there has been no sightings of the rats that might suggest that there is only one or two. Nevertheless, even one rat is one rat too many."

A parent, who did not want to be named, said: "That is disgusting.

"I hope the school is doing everything it can to dispose of the problem. I hope the Health and Safety people are giving guidance.

"I am sure that every parent with children at the school will be concerned. And if the problem continues they would probably have to close the school so it could be thoroughly cleansed."

Governor and councillor Jim Higginson said: "This is a very unwelcome shock for everyone at the school and it is a cause for concern.

"What is extremely concerning is that there is a canteen in the Grayhill building where food is served up.

"Something should be done and done quickly. But I would have thought closing the school would be a last resort measure."

Councillor Olive Evans, vice-chairman of the governors, said she was also concerned.