Thirty bodies have been recovered from the blaze that broke out at a warehouse rave, although authorities believe the death toll reach at least 40. A search of the building has been conducted in only 20% of the building so far and a "significant" number of people are still missing. It's believed around 50 to 100 people were in the building at the time of the fire which started on Friday (3 December).

The fire is being called one of the deadliest single-structure fires in Oakland's history. Almost 55 firefighters tackled the inferno as battalion chief Lisa Baker stated that flames had engulfed three sides of the warehouse. Firefighters were conducting an "aggressive attack" but were forced outside the building due to the ferocity of the flames.

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Firefighters said it appeared that no smoke detectors were activated during the fire and there was no sprinkler system in the structure, Oakland Fire Chief Teresa Deloche-Reed told the East Bay Times.

The roof collapsed on to the second floor, which then fell through on to the ground floor of the ware house, which was packed with furniture, hampering the efforts of firefighters.

"We still have to do a more thorough search of the building and we don't know the potential number of other victims," Oakland Fire Chief Teresa Deloche-Reed said. "This is a true loss for the city, for the firefighters who responded, and the people who lost family and friend. It's just tragic, a real tragedy."

Friends and relatives took to social media to request sightings of the missing. Eveline Darroch wrote: "Hi, I am here with the fire inspector going through the list of missing names of missing/safe. At this point there are several threads. I am requesting that you only post in this thread their name and missing or safe next to it."

Lana Voronina posted: "They are still trying to put out the fire. no communication or sight of people who might still be in there. Waiting here with a group in the parking lot. It's confusing and chaotic."

Oakland Firefighters tweeted: "31st Ave: Fire through the roof, Command requests all units out of the building, going defensive.

"Crews will remain on scene for several more hours. Two ladder pipes and hand lines still deployed extinguishing hot spots."

The club was reportedly hosting a party as part of Golden Donna's '100% Silk' West Coast tour.

The reason for the blaze is as yet unknown. An artists' collective adjacent to the warehouse is also on fire. Smoke was still billowing from an upper floor of the building and the fire has not been officially declared under control. Fire department officials are waiting for the go-ahead from structural engineers before attempting to re-enter the building.