OAKLAND, Calif. (CBS SF) — By the time the partygoers on the second floor of an Oakland warehouse because aware of a fast-moving fire a floor below, their fate was likely already sealed, a federal official said Wednesday.

Special Agent in Charge Jill A. Snyder toured the burned-out warehouse — the scene of the most lethal building fire in the U.S. in more than a decade. In all, 36 people died in the blaze late Friday night at building housing the Ghost Ship artist cooperative.

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“By all accounts,” she said. “The fire started on the first floor. There were two internal stairwells from the second floor that led to the first floor. Neither went to an exit. Smoke traveled up the stairwells, trapping the on the second floor. There was rapid fire progression. Initial witness interviews have indicated the fire was well developed by the time the second floor occupants realized a fire was going on.”

The billowing smoke is what proved so deadly. Alameda County Sheriff’s Sgt. J.D. Nelson said that the completed autopsies had revealed the victims died of smoke inhalation.

“The autopsies so far show the victims died from smoke inhalation,” he told KPIX 5. “It (their deaths) was before any fire or any collapse…If you see the video and you see all that smoke, that smoke is so deadly…it doesn’t take many breathes of smoke like that to put you on the ground.”

Snyder said there was no evidence of smoke detectors or sprinklers in the building.

As for a source of the deadly blaze, Snyder said it was to early to determine a cause and discounted reports linking the blaze to a refrigerator.

“There has been a lot of misinformation lately circulating that the refrigerator was the cause of fire,” Snyder said. “This is not accurate. The refrigerator is still being examined, but has not yet been determined to be the source of the fire.”

She said the ATF investigation into the cause would take “a matter of days.”

Snyder was speaking in front of the warehouse where searchers had ended their painstaking task of looking for victims in the rubble early Wednesday.

While the death toll stood at 36, authorities were not ready to say it was the final total.

The Alameda County Sheriff’s Office Coroner’s Bureau has notified 32 families, an additional 3 notifications are in process and 1 victim needs scientific identification.

Wednesday afternoon, authorities officially identified two more fire victims: 35-year-old Jason McCarty of Oakland and 61-year-old Wolfgang Renner, also of Oakland.

Streets in around the fire scene will re-open as the security perimeter shrinks over the next few hours.

In addition to the previously released names, the Coroner’s Bureau has released the names of two more of the 36 victims:

Like in the 9/11 tragedy, search teams were also carefully sifting through the large piles of debris removed from the warehouse with cadaver dogs for any signs of human remains incinerated in the intense blaze.

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Oakland officials have also declared a local state of emergency for the scene so state and federal funds could be applied for to cover the costs of the recovery.

Continuing Coverage: Deadly Oakland Warehouse Fire

Rep. Barbara Lee on Tuesday night praised first responders for their tireless efforts during the recovery operation. Most of the search team members have said it was a heartbreaking experience they never will forget.

Members of the Alameda County Sheriff’s Department were also consoling a fellow deputy who lost his 17-year-old son in the blaze.

Tearful family members were given a tour of the scene Tuesday by local officials, who also had counselors on site and at a nearby family support center.

The founder of the arts collective that was housed in the warehouse also stood near the gutted building Tuesday morning and said he was “incredibly sorry.”

Derick Ion 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.”

However in a televised interview Tuesday, Almena’s behavior was erratic and he refused to answer question about his possible role in creating the condition for such a fire.

The fire broke out during a dance party Friday night in the cluttered warehouse that was not licensed as a concert site or for living/work spaces.

Oakland city officials were set to release several years of documents involving the building. There were at least three citations issued by building officials over the years including one for illegal construction.

Other complaints were for dangerous conditions, drugs, neglected children, trash, thefts and squabbles at the warehouse.

A building inspector came to the warehouse on Nov. 17 but could not gain access. Oakland Mayor Libby Schaaf said the inspector followed procedure and later sent a request to the owner to gain entry.

The deadly fire has triggered an intense look at other Oakland warehouses where artists have work spaces. Oakland has become a mecca for artists and musicians because of rents more affordable in San Francisco and other neighboring communities.

The district attorney has assigned two set of investigators to the fire to determine if criminal charges will be filed. She said those charges could include multiple murder or manslaughter charges.

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