MORAGA, Calif. --
Police searched unsuccessfully for at least one gunman who opened fire on a East Bay Regional Parks police officer Monday evening.
The officer was patrolling the Upper San Leandro Reservoir Area near Moraga when he came under fire at about 6:40, Capt. Mark Ruppenthal said.
"He was able to return fire at those subjects and hunker down in the area," Capt. Ruppenthal said.
Officers from the Moraga, Orinda and Lafayette Police Departments responded to the scene along with personnel from the California Highway Patrol and Contra Costa Sheriff's Department.
Officers drove an armored vehicle into the park to recover the officer, Capt. Ruppenthal said. The officer was not hurt.
The gunman was not located and authorities stopped searching by 10 p.m. They planned to resume their search Tuesday morning, Capt. Ruppenthal said.
Police said they believe the gunman was guarding a marijuana farm in the heavily wooded area.
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