The Saskatoon Police Service says officers are investigating an assault and fire Thursday at Evan Hardy Collegiate that led to a 15-year-old girl being hospitalized.

Police say they received emergency calls at approximately 12:30 p.m. CST reporting an assault and a fire.

A school resource officer (SRO) who was already on-scene for a different matter arrested a 14-year-old female suspect immediately.

The 15-year-old victim was transported to hospital. She sustained what are believed to be serious injuries.

SROs will continue to work closely with school board officials as the investigation continues.

A Saskatoon Public Schools official said the high school was shut down for the remainder of the day.

Outside the school Thursday afternoon, students could be seen leaving and getting picked up by parents. No one who spoke with CBC News had witnessed the alleged incident.

A news conference is scheduled for 3:15 p.m. CST at Saskatoon Police Service headquarters.