SAN JOSE (KPIX 5) — San Jose Police are working with the FBI and Santa Clara County crime labs to analyze a bomb that was planted at Oak Grove High School Tuesday and whether the device holds any clues that can help lead to a suspect.

“It was a functioning explosive device so we are very concerned and asking if anyone has any information to contact us,” said Officer Gina Tepoorten.

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Sources tell KPIX that the device was about the same size as a handheld radio or a cell phone and that it was wrapped in tape. It was also described as having what looked like a fuse coming out of the top. It may have been filled with some type of liquid.

The maintenance worker who found it apparently did not think that much of it and took it to the administration office where others recognized it as a potential explosive device and called police.

The San Jose bomb squad eventually secured the device and safeguarded so that it could no longer blow up. Meanwhile, the school was put on a shelter-in-place.

“Some were like scared and nervous, I told them, like, we’ll be OK,” said senior Carlos Mejia.

The students were later evacuated to a nearby park. Police say it was good that the maintenance worker found the device, but emphasized he should have just left it alone.

“Anytime someone sees something that could be a destructive device, we ask that you leave it where it’s at, don’t touch it, and immediately call police,” Tepoorten said.