Investigators have found 36 bodies so far as they continue to search the remnants of a two-story converted warehouse following a deadly fire Friday night. As of Sunday, they had searched about a third of the two-story building. Authorities have started to identify some of the victims and said they expect the number of bodies to grow. Among the dead are teenagers as young as 17.

The fire started during a concert at the converted warehouse known as the “Ghost Ship.” According to news reports, the building had been converted into a maze of artist studios, and some people were reportedly living on the premises illegally. The warehouse did not have the appropriate permits for people to live in it.

There may have been up to 100 people at the concert when the blaze started. Authorities say the roof collapsed onto the second story, and part of the second story collapse onto the first story. Given the conditions, emergency responders were unable to enter the building even after firefighters had put out the flames.

Former Occupants Describe “Death Trap”

Former occupants have shed light on the conditions on the property, with many pointing to clutter that fire officials say helped fuel the fire. Some told Fox News that the warehouse “was a cluttered death trap with few exits, piles of wood and a mess of snaking electric cords.” Many are noting that the warehouse contained no fire sprinklers and no fire alarms. And reports suggest that at least one of the two-story building’s exits was a staircase consisting of wooden pallets.

Shelley Mack, a former occupant of the warehouse in 2014 and 2015, said there were several mobile homes parked inside the warehouse that people would rent out, reports the Los Angeles Times. She also said that occupants of the warehouse used an illegal electrical hookup to get electricity.

Records show that the city was already investigating complaints of trash and debris that piled up outside the structure. The city had also received complaints of an illegal construction in the warehouse. According to the city, inspectors were unable to gain access to the building when they went to investigate. There was also an investigation into whether people were illegally living on the premises.

Cause of Fire Still Under Investigation

Investigators have not yet identified the cause of the fire. The district attorney launched a criminal investigation and the city has created an arson task force.

Whatever the cause, descriptions of the conditions in the building – no fire sprinklers or alarms, questionable exits, excessive clutter – suggest it was not equipped to serve as a residence, let alone host such a large party.

Meanwhile, authorities say that the process of identifying the remains found in the building could take weeks. They are asking family members of missing persons to preserve samples of loved ones’ DNA, such as hairbrushes or toothbrushes.

Burn Victims Resource contains several pages and materials that survivors and families may find helpful: