The Associated Press
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DAVIS, Calif. — A student was in custody Thursday after the discovery of explosive devices at the University of California, Davis.
Two partially assembled pipe bombs were found in the student's dorm room, university spokeswoman Lisa Lapin said. Authorities believe it was an isolated incident and said there was no need to detonate any devices.
More than 450 students were evacuated Wednesday night from eight dormitories and slept in dining halls or at the homes of family and friends. Everyone had been let back in by early afternoon, and no classes were canceled.
Police became aware of the situation Wednesday night after a woman reported that students had possible explosive devices.
Students were evacuated immediately, but police saw no imminent danger of an explosion and waited until Thursday morning to get a search warrant, which requires a judge's signature.
After questioning four students, police arrested 18-year-old Mark Woods, a freshman economics major from Torrance. Lapin said he has been cooperating with authorities.
A roommate said Woods was curious and liked to experiment but was a serious student and would have had no criminal intent, Lapin said.
No other arrests were expected.
"Police investigators say there is nothing to indicate that this case was related to a terrorist act," a university statement said. "The investigation is continuing."
Woods was being held on possession of materials with the intent to make an explosive or destructive device, as well as possession with intent to make such a device on school grounds.
Investigators carted off about five milk crates full of material from his room, mostly powdered substances, Lapin said.
Woods was being held Thursday afternoon at the Yolo County Jail. His bail was set at $100,000.
University officials were in the process of temporarily suspending him as a student. They will decide whether to suspend him permanently after the legal proceedings are over.
It was not clear whether Woods had retained an attorney, and a call to the Yolo County Public Defender's Office was not immediately returned.