A law enforcement official says a man has been arrested for allegedly causing a massive inferno that destroyed an unfinished apartment building and damaged adjacent office towers in downtown Los Angeles.

The official with knowledge of the investigation says 56-year-old Dawud Abdulwali, of Los Angeles, was arrested Wednesday. The official wasn't authorized to speak ahead of a 6 p.m. news conference and spoke on condition of anonymity.

The motive is unknown.

The Dec. 8 fire gutted the 1.3-million-square-foot complex that was in the wood-framing stage. It went up like a huge bonfire visible for miles.

The fire's heat cracked or shattered hundreds of windows in neighboring buildings, ignited small fires in one, and damaged an adjacent freeway.

Damage was estimated at $20 million to $30 million. No one was hurt.