The shooter was later killed by police.

Ten people were also injured as the perpetrator randomly shot at people.

However, Tehama County Assistant Sheriff Phil Johnston said that a bigger killing has been averted due to the quick thinking of the staffs of Rancho Tehama Elementary School.

After the staffs heard gunfire, they moved back all the kids and bolted the classroom doors.

The attacker later rammed through the school gate but left six minutes later after he failed to notice anyone.

"This individual shooter was bent on engaging and killing people at random. I have to say this incident, as tragic and as bad as it is, could have been so much worse," Johnston said.

He added, "This is an individual who armed himself, I think with the motive of getting even with his neighbors and when it went that far, he just went on a rampage."

Police have also added that they are yet to find a motive and have asserted that his victims were picked at random.