A 27-year-old man was arrested after police said he was in possession of 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 this investigation into the vandalism, Pleasant Hill police say they uncovered evidence showing 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 bomb squad and Clayton police, executed a search warrant in the 300 block of Longbrook Way.
Police found explosive materials and an explosive device and many residents were evacuated.
Officials said Contra Costa Hazmat County along with ConFire Hazmat and the FBI responded to help with the investigation.
Police said the suspect was arrested without incident and taken to the county jail. The scene was secured and the evacuation order was lifted.
The case is still ongoing.
Anyone with information is asked to contact the Pleasant Hill Police Department at 925-288-4600.