A 27-year-old man was arrested Friday after Pleasant Hill police said they found bomb-making materials and explosives.
According to the Pleasant Hill Police Department, their detectives along with the Clayton Police Department were actively investigating a series of vandalisms, which occurred in both jurisdictions.
During that vandalism investigation, Pleasant Hill police said they uncovered evidence that showed the suspect was in possession of bomb-making materials and explosive devices.
At 3 p.m., Pleasant Hill police said their officers along with the Walnut Creek Police Department's bomb squad and Clayton police, executed a search warrant on the 300 block of Longbrook Way.
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Police said they found explosive materials and an explosive device and about 20 residents from an apartment complex were evacuated.
Officials said Contra Costa County Hazmat along with ConFire Hazmat and the FBI assisted with the investigation.
Police said that the suspect was arrested without incident and booked into County Jail. The scene was made safe and the evacuation order was lifted.
The investigation is still ongoing.
Anyone with information is asked to contact Pleasant Hill police at 925-288-4600.