San Bernardino County sheriff's deputies received the call Wednesday morning from the Los Osos High School in Rancho Cucamonga and immediately launched an investigation, a statement from the San Bernardino County Sheriff's Department said.
The assistant, an adult male from Ontario, was detained and removed from the school, the statement said.
Video evidence will be turned over to the district attorney's office for review as investigators seek charges, the statement said.
Anyone with information regarding this investigation is urged to contact the Rancho Cucamonga Police Department.
Callers wishing to remain anonymous can call the WeTip Hotline at 1-800-78-CRIME (27463), or leave information at www.wetip.com.