A gunman killed 12 people including a sheriff’s deputy after he walked into a Southern California bar and started shooting late on Wednesday night, police said.The gunman was also killed, Ventura County Sheriff Geoff Dean told a news conference early on Thursday, though it was not immediately clear by whom.An unknown number of people were wounded during the attack at the Borderline Bar and Grill, a country & western venue in the Los Angeles suburb of Thousand Oaks.“It’s a horrific scene in there,” Dean said.