UPDATE: Officials Determine Cause Of Fire At Temecula Valley High School

UPDATED at 2:07 p.m.

The cause of Wednesday's fire at Temecula Valley High School on Rancho Vista Road that prompted an evacuation has been determined, an official has announced.

During an auto shop class at the campus Wednesday morning, students were working on a vehicle that backfired and sparked the blaze.

"Firefighters responded to a fire in the wall of the auto shop ... the cause of the fire was determined to be from hot carbon particles from a vehicle backfire into the exhaust system," said Jody Hagemann, Cal Fire/Riverside County Fire Department spokeswoman.

The fire was reported at 10:03 a.m. and was contained at 10:33 a.m., according to Hagemann.

No injuries were reported.

The loss was estimated at approximately $10,000 with an estimated save of $4,000,000, Hagemann said.

Approximately 500 students were evacuated prior to firefighter arrival. All students and TVHS staff were eventually evacuated from the campus, confirmed Temecula Valley Unified School District spokeswoman Melanie Norton.

The evacuation lasted for more than an hour as school officials waited for fire crews to deem it safe to return to classrooms.

At 11:50 a.m., Norton confirmed students and staff had returned to campus.

The Riverside County Sheriff’s Department was called to assist with traffic control at the scene, according to Deputy Albert Martinez.