School officials received reports that a bomb was on the Spartan campus, San Bernardino police spokesman Lt. Paul Williams.
Williams said the San Bernardino City Unified School District police were the primary law enforcement agency in the incident.
"The Colton police recieved reports of the bomb threat," said San Bernardino City Unified School spokeswoman, Linda Bardere. "They contacted the San Bernardino police who then informed school police."
The school police along with school officials, conducted a fire drill to get the students out of the classrooms and onto the football field without panicking them.
San Manuel Tribal police responded to the school with there bomb detail to search the campus.
No device was found and the threat was ruled a hoax.
"The students were safe and released from their classes on time," said Bardere.
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