A 16-year-old girl has been arrested on suspicion of attempted murder at her school.
A 61-year-old welfare officer at Winterton Community Academy in North Lincolnshire suffered non-life threatening stab wounds in an incident on Monday morning, Humberside Police said.
The teenager, who is a student at the Academy, is being questioned by officers.
Chief Superintendent Christine Wilson said: “We attended a serious incident just before 9am this morning at Winterton Community Academy, and a 61-year-old woman is being treated in hospital for serious but not life-threatening injuries.
“Staff at the school and police officers responded to this isolated incident very quickly, and one person is currently in custody as a result.
“There was no disruption to any other children, non of whom witnessed the incident. Children at the school have not been directly affected by this.”
Headteacher Gareth Morris said: “We are keen to reassure parents and the community that this is an isolated incident and that the school remains open.
“We will support our staff directly affected and will be keeping parents updated throughout the day.”