An English school has been forced to close after an outbreak of "false widow" spiders, the latest in a series of sightings of Britain's most poisonous arachnid.

Dean Academy in the western Forest of Dean region will shut its doors while experts deal with the eight-legged invaders, vice principal Craig Burns said.

The spiders, which resemble the potentially deadly black widow, have colonised parts of southern England for more than a century.

However, they are thought to have spread in the past 25 years, according to Britain's Natural History Museum.

Their bite can cause swelling or fever.

So far, no one at the school has been bitten, Mr Burns said.

There have been numerous reports of false widow sightings and attacks around Britain in recent weeks.