At least nine people died and 25 were missing after a fire broke out during a party at a warehouse in the US state of California, local media reported Saturday, dpa reported. The fire was reported shortly before midnight on Friday at the two-storey building in Oakland, California, which housed artists and their studios as part of a collective, local newspaper East Bay Times reported. About 50 people were inside the building, firefighters told local news channel KTVU. A video posted by firefighters showed thick smoke billowing from the building engulfed by large flames. The cause of the fire remains unclear.