OAKLAND (CBS SF) – Federal investigators have yet to find a cause of the deadly fire that quickly swept through a warehouse filled with a makeshift maze of artists spaces and killed 36 people attending a music event on the second floor, authorities said Tuesday.

Jill Snyder, special agent in charge of the San Francisco office of the Bureau of Alcohol, Tobacco, Firearms and Explosives, said her agency had concluded its exhaustive inspection of the burned-out remains of the two-story building.

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“No final determination (of a cause) has been made at this point,” Snyder said.

Investigators earlier had ruled out a refrigerator and other appliances inside the building as a possible source of the intense three-alarm blaze.

Oakland Fire Chief Teresa Deloach-Reed said there was no record of the warehouse anywhere in her department’s database and that the building had never been inspected.

“We have checked our records,” she told reporters Tuesday. “We even went back to our old system…We pulled our records for any dispatches, calls for service…We don’t have any record stating our firefighters ever made entry.”

Deloach-Reed said the state doesn’t not mandate inspections of warehouses and that her department had no knowledge it was being used as a living/work space. She said her department had never fielded any complaints from the public about the building.

“We have no record of 1315 31st Ave. ever being inspected,” she said. “Nor do I have any record of their applying for a special permit, a change of occupancy, any type of tenant improvement which is types of construction. None of these areas that would have triggered the facility to be in our system.”

Continuing Coverage: Deadly Oakland Warehouse Fire

The fire started out at the rear of the building and spread so quickly that the fate of the 36 victims on the second floor had already been sealed by the time they likely smelled the smoke and became away of the fire, Snyder said.

Alameda County Sheriff’s Department officials have said that the autopsy showed that most victims had died of smoke inhalation and not of burns or injuries suffered by the collapse the roof onto the second floor.

The building – housing the Ghost Ship artist cooperative – was zoned for use only as a warehouse. It was not given permits that would have allowed people to live there or for it to host music events.

Several complaints had been made to Oakland building officials about the warehouse from neighbors and others. Included was one for illegal construction inside the building.

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A city building inspector has visited the warehouse on Nov. 17th but could not gain access.

Two teams of investigators from the Alameda County District Attorney’s Office have been reviewing evidence, city building records and interviewing survivors to determine if criminal charges will be filed in the deadly fire.

District Attorney Nancy O’Malley said charges could include multiple murder or manslaughter counts.

Her office is asking anyone who has information about the Ghost Ship warehouse or the fire to call their hotline at 1-877-288-2882.

Meanwhile, memorial services for the victims began on Sunday and would continue for some time.

At the Sunday funeral for video artist Jonathan Bernbaum from Berkeley, his father recalled the last time he saw his son it ended with a warm embrace.

“I miss him terribly and feel so sorry for the bright life that was extinguished and the terrible way he died,” he said. “His last hug will always be a great solace.”

At a weekend memorial for the youngest victim, classmates at the Ruth Asawa School of the Arts sang somber tributes to Draven McGill.

McGill is the son of a deputy for the Alameda County Sheriff’s Office which added to the emotional stress for the first responders searching the wreckage of the building for victims.

“Draven was and always will be family for us,” said Kristen Grzeca, a music teacher at the school. “Whether we knew him for three months, three years or 13, the time and music we shared has created a bond stronger than death.”

On the Sarah and Vinnie Show on Alice Radio Tuesday, local recording star Michael Franti join in a tribute to the victims.

He said he once lived in a warehouse near the site of the fatal fire as a struggling artist himself.

“As a musician nothing is worse than bringing a group of people together to celebrate life and have a great time … and then someone gets hurt, someone dies… People are so quick to point fingers but first we got to stop and remember and acknowledge the people (who died). The families and friends (of those who died) are going through hard times. Especially with the holidays.”

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