An invasion of venomous spiders has closed a secondary school in Gloucestershire after they were discovered in the ICT block.

The infestation of the dangerous "false widow" spiders at the Dean Academy in Lydney, Gloucestershire, forced senior staff to close the school on the advice of health and safety officers at Gloucestershire county council and pest control experts drafted in from Chepstow.

The spiders were first discovered at the academy on Monday afternoon. The entire ICT block was closed on Tuesday to allow fumigation to take place.

As more spiders were discovered elsewhere in the school, there was no choice but to close the academy to allow further pest control to be carried out.

A letter was sent out to all parents from vice principal Craig Burns, who said the decision had been taken in the best interests of the students' health and safety.

Burns, who stressed that there had been no reports of anyone being bitten by spiders, wrote: "We identified an issue with 'false widow' spiders in the academy in our ICT block yesterday afternoon and therefore took immediate advice from pest control.

"We therefore made the decision to close the ICT block for the whole of today so that pest control could fumigate the area.

"Unfortunately, during this afternoon there have been further 'false widow' spiders identified in other areas of the academy."

The false widow (Steatoda nobilis) is about the size of a 50p coin and is the most dangerous of the 12 species of biting spider known in Britain. There have been no reported deaths from its bite in the UK.

Symptoms can include severe swelling, chest pains and tingling of fingers, with the severity depending on the amount of venom injected.