Mission Elementary students and teachers arrived Wednesday morning to find the work of vandals -- shattered glass doors, TVs and computers, a white powder covering the office and a classroom's pet turtle missing.
Police are investigating the vandalism, which displaced students in three classrooms.
Little was taken, but preliminary estimates put the damage done to the school at $20,000.
The office and teacher lounge were coated with white residue from fire extinguisher spray, Principal Sylvia Birdsell said. The panel that controls the public announcement system, bells and clocks was bashed in. Rocks were apparently thrown through glass classroom doors to break in, Birdsell said.
"It was devastating to the children, to the staff, to the entire community," she said.
"They didn't just steal things, they destroyed," she added.
Although the school has an alarm system, it appears no one responded. The alarm went off between 3 a.m. and 4 a.m., according to Antioch schools Superintendent Dennis Goettsch. The district contracts with Guardian Security to respond to the alarm and determine whether to call the police.
But police say they were not notified until school employees called at 7:10 a.m. on Wednesday.
"It's my understanding that the alarm company notified the (security company) and they didn't respond," he said. "In talking with the security company, I believe that it's their responsibility to pay for the damages."
Guardian Security officials could not be reached for comment late Thursday.
Goettsch said the security company is investigating the incident.