TORONTO (Reuters) - Eight people were injured and a female student was in custody after a stabbing at a Canadian high school east of Toronto, police said on Tuesday.

One of the people had serious but not life-threatening injuries, while the others had minor injuries, Durham Regional Police said in a series of posts on Twitter.

Dunbarton High School, in the Toronto suburb of Pickering, was locked down for several hours but students have since been allowed to leave.

Police said four people were taken to hospital to be treated, and the wounded included two staff members.

“It was two staff members who were actually able to stop the attack from happening,” Durham Regional Police Sgt. Bill Calder told reporters.

“There is no known motive right now,” he added.

Four people, including two students and two teaching staff, were killed in January during a school shooting in a remote northern community in Saskatchewan in Canada’s worst school violence in a decade. A teenager has been charged in the incident.