Walnut Creek Murder: Standoff In Martinez Ends With Surrender After 19 Hours

EAST BAY, CA — A 38-year-old man who was wanted on suspicion of murdering his girlfriend in Walnut Creek briefly surrendered after a 19-hour standoff in Martinez, police say. About 1:15 p.m. on Friday, the unidentified man emerged from his car with his hands over his head shortly after loud bangs resembling gunfire were heard.

But then the suspect, Gregory Prokopowicz, got back into the car — this time on the passenger side of the vehicle — before peacefully surrendering a short time later, according to Martinez police. Prokopowicz has known addresses in both Martinez and Walnut Creek.

Police say at about 1:30 p.m. Thursday, the Walnut Creek Police Department received several reports that a 47-year-old female had been shot in the street near the Lyndsay Wildlife Experience. Officers arrived on scene and attempted life saving measures however, she did not survive and was pronounced dead 15 minutes later. The suspect and victim had dated, according to police. She has been identified as Roselyn Policarpio, with last known addresses in Martinez and Stockton.

Just before 7 p.m., two Walnut Creek Police officers spotted the suspect riding in the front passenger seat of a silver Mercedes in Martinez. They stopped the car and detained the driver. That's when police say Prokopowicz put a gun to his head and said he was going to harm himself. Central County SWAT negotiators arrived 20 minutes later. The negotiations continued and at one point, the suspect accidentally fired his handgun through the windshield, but no one was hurt.

Streets in the area that had been blocked during the incident have now reopened, police say.

Bay City News contributed to this report/Image via Walnut Creek Police