4 people killed in Halloween party shooting in California

Four people were killed and at least another four injured in a shooting at a house party Thursday night in the San Francisco Bay Area, Police Chief David Cook of Orinda, California, tells CNN. Police were "being overwhelmed by the crowd where the shooting happened" on Halloween night, they told CNN affiliate KPIX. The Contra Costa County Sheriff’s Office announced the casualties in a tweet on Friday, Nov. 1. It said it is working with the police department in the city of Orinda, where the shooting took place. Neither department has released further details.