Investigators said Tuesday a warehouse fire in Oakland that killed 36 people did not appear to have been set intentionally and may have been caused by a refrigerator or other electrical appliance.

Details about a possible cause emerged as fire crews nearly completed their search for bodies in the most lethal building fire in the U.S. in more than a decade. The death toll remained at 36 and was not expected to go higher.

Tearful family members visited the scene and exchanged hugs hours after the founder of the arts collective that used the warehouse stood near the gutted building and said he was “incredibly sorry.”

“Everything that I did was to make this a stronger and more beautiful community and to bring people together,” Derick Ion Almena told the “Today Show” on NBC.

Almena said he was at the site to put his face and his body in front of the scene, but he deflected blame for the blaze, saying he signed a lease for the building that “was to city standards supposedly.”

The fire broke out during a dance party Friday night in the cluttered warehouse. It had been converted to artists’ studios and illegal living spaces, and former denizens said it was a death trap of piled wood, furniture, snaking electrical cords and only two exits.

A refrigerator was a potential source of the fire, but it was too soon to say for sure, said Jill Snyder, special agent in charge of the San Francisco office of the Bureau of Alcohol, Tobacco, Firearms and Explosives.

Snyder said investigators were looking at “anything electrical” on the first floor of the warehouse near the origin of the blaze.

“We have no indication that this was intentionally set,” she said.

Almena did not respond to emails or calls to phone numbers associated with him by The Associated Press. He told San Jose television station KNTV that he didn’t attend the event Friday night and that he and his wife had decided to stay at a hotel because he was exhausted.

City and state officials fielded years of complaints about dangerous conditions, drugs, neglected children, trash, thefts and squabbles at the warehouse, raising questions about why it wasn’t shut down. The district attorney warned of possible murder charges as she determines whether there were any crimes linked to the blaze.

Oakland Mayor Libby Schaaf released late Tuesday records from the city’s planning and building department on the warehouse and adjacent lot that includes complaints going back to 2005.

“I am not prepared to draw conclusions from the history,” Schaaf said. “We are still in the process of compiling it.”

Crews had searched 90 percent of the building known as the “Ghost Ship” for bodies as of Tuesday afternoon and were expecting to complete the rest of the search by midnight. Fire officials started knocking down parts of the building that they said were structurally unsound.

Alameda County sheriff’s Sgt. J.D. Nelson said of the 36 victims found, 35 have been identified and 20 of their families have been notified. Officials are still lacking any type of identity for one person.

Stories of the victims’ last minutes, meanwhile, emerged.

Alameda County sheriff’s spokesman Sgt. Ray Kelly said that some of the victims texted relatives, “I’m going to die,” and “I love you.”

Rescue crews found bodies of people “protecting each other, holding each other,” Kelly said.

(AP)