As many as 120 firefighters battled the fire, which was declared knocked down at 3:45 p.m.
Davies said the cause of the fire and the full extent of the damage was not known, but she said "most of the fire was in the attic. There was a lot of water damage in the underneath."
Residents watching the building the burn said the flames may have been set off by workers in the attic, or in one of the units that was being renovated.
Davies said firefighters who first arrived on the scene found the attic fully involved in flames.
Some firefighters stood on the roof of an adjacent building, dousing the flames with water, but the fire appeared to have destroyed at least half of the U-shaped structure.
Firefighters were pulled out of the building as the roof continued to burn and collapse. Other crews checked adjacent buildings to ensure that the fire did not jump to any other structures.
An unknown number of people were evacuated from the building, and both Detroit and Sixth streets and La Brea Avenue and Wilshire Boulevard were closed in the area, snarling traffic at the onset of the afternoon rush hour.
City News Service contributed to this report