At least nine people at Tomas Rivera Middle School in Perris were sent to the hospital and students were told to shelter in place after a car crashed into a school building Wednesday.
Three people suffered moderate injuries while six others had minor injuries, the Riverside County Fire Department said.
Val Verde Unified School District Police Department said no students were hurt and all those injured were staff members.
There was an ongoing investigation as to why the car crashed into the building located at 21675 Martin St.
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The crash occurred at 1:5 p.m. when a red Toyota Corolla slammed into the building, ending up completely inside the structure through a wall.
Drugs and alcohol are not suspected as a cause of the crash, but CHP is investigating and asking any witnesses to contact investigators at (951) 637-8000.