OAKLAND (CBS/AP/BCN) -- California Gov. Jerry Brown issued a statement of condolences after a deadly fire in Oakland left at least nine people dead.
Brown said in the statement that he and his wife, Anne, were saddened to hear about the deadly blaze.
CONTINUING COVERAGE: Deadly Oakland Warehouse Fire
In the statement Saturday he said: "Our thoughts are with the entire city in this difficult time and we extend our condolences to the family and friends of those lost."
Authorities say they fear up to 40 people might have died in the fire at a warehouse converted into artist studios that was hosting an electronic dance party.
Rescue crews were combing through wreckage and still trying to access parts of the warehouse mid-day Saturday.
Oakland Mayor Libby Schaaf issued a separate statement calling the fire "an immense tragedy."
"I am grateful to our first responders for their efforts to deal with this deadly fire. Our focus right now is on the victims and their families and ensuring that we have a full accounting for everyone who was impacted by this tragedy," Schaaf said in the statement. "The most critical information to share at this time is the phone number where victims' families can get information which is (510) 382-3000 at the Alameda County coroner's bureau."
Saturday morning, firefighters remained at the scene, preparing to enter the warehouse to begin the recovery process.
Sheriff's office spokesman Sgt. Ray Kelly said the coroner's office is waiting for firefighters to make the building safe and put out any remaining hotspots. He said they hope to get into the building by about noon.
During the fire, a part of the building's roof collapsed and fell onto the second story floor, according to Kelly.
Twenty-five people remained unaccounted for.
"A lot of these people were young people that were inside of this building," he said. They are from all parts of our community." Kelly said, adding that many of the victims were from outside of the Bay Area.
The cause of the fire is still under investigation.
"We will be at the scene for days to come as we try to make sense of what happened here," according to Kelly.
The fire broke out at the two-story warehouse located at 1305 31st Ave. at around 11:30 p.m.
"There is still a large portion of the building that needs to be searched," Oakland fire Chief Teresa Deloach Reed said.
The setup inside the building initially made it hard for people to escape. Partitions and other structures inside the warehouse made exiting more difficult, according to Deloach Reed.
She said there appears to have been only one stairwell leading from the first to the second floor. That makeshift staircase appears to have been made from pallets, she said.
"If the fire started in that area, then everyone on the second floor would have not been able to escape," Deloach Reed said. "I don't know where the fire started, but I know the way the building was situated, it really made it difficult for people to escape."
People who managed to escape the blaze gave firefighters a list of people who were unaccounted for. Deloach Reed said she doesn't believe paramedics transported any injured people to the hospital.
The building is a live/work space, according to the Oakland police department.
A party with musical acts was happening at the warehouse when the fire broke out.
Police are asking anyone looking for missing persons associate with this fire to contact the Alameda County Sheriff's Coroner's Bureau at (510) 382-3000.
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