A 13-year-old girl is due in court today after staff and pupils at a school were allegedly threatened with a 12-inch kitchen knife.
The agitated youngster was said to have started 'stabbing a white board' and making threats.
Teachers reportedly managed to remove the knife from the teen and get her into a room away from other youngsters at Penair School in Truro, Cornwall.
During the incident, one of the teachers at the school was injured, after being head-butted by the pupil.
The girl was arrested at the scene after police arrived on Monday afternoon and was kept in custody overnight.
The teenager, who can not be named for legal reasons, will appear at Truro Magistrates Court today.
She has been charged with the offences of threatening to kill, possession of an offensive weapon, assault and criminal damage.
Parents were originally alerted to the incident by a text sent out from the school on Monday.
Penair School is an academy with just 115 pupils aged between 11-16.