At least nine people have died in a fire during a club night near San Francisco, authorities say.

Authorities said they were preparing for the death toll to rise as high as 40.

The fire started at 23:30 local time on Friday (07:30 GMT Saturday) in Oakland, police told the BBC.

The venue was hosting a concert by electronic group Golden Donna. The event’s Facebook page indicates a number of people are missing.

Oakland fire chief Teresa Deloche-Reed said the building contained between 50 and 100 people when the fire started.