OAKLAND, Calif. (AP) -- A man who illegally rented out space in an Oakland, California, warehouse that caught fire and killed 36 people has been arrested and will be charged with involuntary manslaughter along with an organizer of a party at the site, a source close to the investigation told The Associated Press on Monday.
The Alameda County district attorney said she will formally announce charges later in the day.
The person says Derick Almena and Max Harris will each be charged with 36 counts of involuntary manslaughter. The source was not authorized to publicly discuss the charges and spoke on condition of anonymity.
Authorities say Almena leased the warehouse and illegally sublet space for artists to live and work. He is also accused of holding for-profit concerts at the warehouse, which was not licensed for entertainment.
Harris lived at the Ghost Ship and is accused of helping plan the December concert where the fire broke out.
The building was licensed as a warehouse only and not for entertainment or residency.
More than six months after the fatal blaze, authorities have not disclosed what caused the fire but have said they are investigating electrical causes.
Kyndra Miller and Jeffrey Krasnoff, attorneys who represent Almena, did not immediately return phone messages Monday. It's not known if Harris is represented by an attorney.
Oakland city records show neighbors, residents and visitors repeatedly complained about the warehouse to city officials, citing safety problems, loud parties and other issues with the dilapidated building that had been illegally converted into living spaces.
Firefighters and other city officials were called to the property and adjacent buildings. No citations were issued.
Relatives of half the victims who died in the fire have filed wrongful death lawsuits against Chor Nar Siu Ng, the building's owner, and Almena, who held the lease. The lawsuits also name Pacific Gas & Electric, alleging the utility should have known the warehouse was wired hazardously.
Almena quickly became the focal point of widespread anger and criticism after the fire. Past residents of the warehouse accused Almena of ignoring hazardous living conditions and putting profits over safety. Visitors described the structure as a warren of scrap wood, sofas, old pianos and snaking electrical cables.
Hours after the fire, Almena posted a comment to his Facebook page that stoked the anger.
"Everything I worked for is gone," Almena posted.
Almena later said he didn't know people had died when he posted the comment.
Four days after the fire, Almena gave a brief, rambling interview with NBC's Today show. He was asked about charging for concerts and subleasing space.
"Profit?" Almena asked host Matt Lauer rhetorically. "This is not profit, this is loss. This is a mass grave. I'm only here to say one thing, that I am incredibly sorry and that everything I did was to make this a stronger, more beautiful community and to bring people together."
Lauer cut the interview short after Almena became combative when asked if he should be held responsible for the deaths.
Almena also lived in the warehouse with his wife and three young children, but was staying the night in a nearby hotel the night of the fire.
Associated Press writer Janie Har contributed to this report.