The issue of school violence took a surprising turn at one California high school.

A security guard at Oakland High School was caught on camera punching a student in a wheelchair on May 19.

The guard, identified as Marchell Mitchell, has been arrested, was urging students to hurry to class when he had a disagreement with the wheelchair-bound student that led to him attacking the teen. Francisco Martinez, 17, who suffers from cerebral palsy, spat on Mitchell before the guard retaliated by hitting him several times and dumping him on the floor.

Injuries were so bad Martinez had to go to the hospital, although he is expected to recover.

The school's principal wrote a letter to parents condemning the incident. It said, in part, “I’m shocked and deeply hurt by this behavior and apologize on behalf of the staff at Oakland High. This incident is not reflective of the kind of culture we cherish at our school or how we treat one another."