Ventura County Sheriff's Office Capt. Garo Kuredjian said at a news conference early Thursday that a sheriff's deputy was also shot and taken to a hospital. He could not immediately provide information on the extent of the victims' injuries.
He said responding deputies could hear gunshots as they arrived on scene.
Authorities are still treating it as an active shooter scene.
No other information was immediately available.
Police tell the Ventura County Star that the initial report came around 11:20 p.m. that a man opened fire at the Borderline Bar & Grill in Thousand Oaks, which is about 40 miles west of Los Angeles. The extent of the victims' injuries wasn't immediately known.
Ventura County Sheriff's Office Capt. Garo Kuredjian said late Wednesday that it was still "a very active scene." Witnesses tell ABC News that a man fired several shots from a handgun before tossing smoke bombs and starting to fire again.
Police tell the Los Angeles Times that at least 30 shots were fired.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)