Police have shot a parent who held a 70-year-old teacher hostage for hours at his daughter's Southern California elementary school.

The incident started around 11:00AM and a SWAT team was in place attempting to make contact with the suspect.

Riverside police Officer Ryan Railsback says that after a stand-off that lasted several hours the SWAT team entered a classroom at Castle View Elementary School shortly before 6 p.m. The suspect was disarmed, however his condition was not immediately known, AP reports.

Railsback says negotiators were forced to storm the classroom as they hadn't heard from the teacher and feared for her life.

Family members identified her as 70-year-old Linda Montgomery. Police say the teacher was taken to a hospital but didn't appear to have any serious injuries.

It's still not clear what prompted the man to enter the school and barricade himself with the teacher Tuesday morning and it's not known whether he had a weapon.

In a post on the Riverside School District's Facebook page, authorities confirmed that all the students had been safely evacuated and accounted for.