ALAMEDA (CBS SF) — A possible explosive device was found at Crown Memorial Beach in Alameda Sunday morning, East Bay Regional Park District police said.

The device was spotted by a park ranger who was doing maintenance work in the area around 10:30 a.m. near the restrooms at Shoreline Drive and Park Street, according to Lt. Jon King.

Park police officers responded and determined the suspicious item was a possible explosive device, King said. Portions of Crown Beach, Shoreline Drive and Park Street were closed during the investigation.

The Alameda County bomb squad responded to the scene and confirmed that the device was potentially explosive in nature. The device was safely detonated in place, and no injuries or damage occurred as a result, King said.

The park and all streets have been reopened. The incident remains under investigation.

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