Arson investigators from the Los Angeles Fire Department and the Bureau of Alcohol, Tobacco, Firearms and Explosives were to begin inspecting the site on Wednesday.
The blaze was reported at 1:20 a.m. Monday on the 900 block of West Temple Street. The bulk of the fire was knocked down after about 90 minutes, but it took several hours to control the fire. At its peak, 250 firefighters were on scene.
Two nearby city-owned buildings were affected by the fire. A 16-story high-rise building at 221 North Figueroa was exposed to the flames, causing an active fire on three floors. Another high-rise at 313 North Figueroa was also exposed, but no active fire was reported there.
Flames spread across the 110 Freeway, damaging highway signs and melting the asphalt. Scaffolding from the construction site fell onto the freeway, which was closed for most of the day.
The California Highway Patrol reopened the transition road from the northbound 110 Freeway to both directions of the 101 Freeway downtown at about 5:15 p.m., according to Caltrans. A SigAlert was canceled for the northbound 110 Freeway and on-ramps through downtown L.A. shortly after 9 p.m. Monday, but the far right lane near 2nd Street remained blocked.
Most of the Da Vinci apartment building was destroyed by the fire. Fire crews were still dousing hot spots at the scene on Monday afternoon.
There were no reports of injuries. The cause of the fire remains under investigation.
L.A. Fire Captain Jaime Moore said firefighters were dealing with falling glass from a neighboring building as the heat shattered windows early Monday.
"The fire was so large that the radiant heat caused windows on two adjacent buildings to explode," said Moore.
The closest fire station was a block away. The fact that the fire spread so quickly leads fire investigators to suspect that an arsonist could be to blame.
"The inclination, when we come out and we see a fire this well-developed in an area where a lot of people are passing by and maybe prudence would dictate somebody would have called, is perhaps it was set," said L.A. Fire Deputy Chief Joseph Castro.
There was no construction activity overnight at the location. Workers are typically gone all weekend, leaving minimal chance that anything was left smoldering at the site. The wood frame was still soaked from recent rains.
"It had been wet," said Captain Moore, a former arson investigator. "It had been saturated with water."
The building's two base floors made of concrete, even harder to ignite than wood, were also engulfed.
"It's very rare for the entire building to be on fire simultaneously," said Moore. "And that was the case this morning."
"These fires are really very rare, they truly are," said Castro. "We haven't had one of this nature in a long time."
Later Monday, it was announced the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) National Response Team would join in the investigation by request in an effort to gather evidence from the large scene.
"We will partner with the Los Angeles Fire Department and provide our expertise as a force multiplier to determine the origin and cause of this fire," said Carlos A. Canino, Special Agent in Charge of the ATF Los Angeles Field Division.
The LAFD said it would be Wednesday at the earliest before the National Response Team is present and all investigators enter the structure together. Twenty arson experts were expected.
VIDEO: Downtown LA buildings damaged in massive fire
The Department of Recreation and Parks and the Department of Building and Safety were most affected. Because of the fire, no one was able to get permits for any type of construction on Monday.
"The north tower was damaged. The flames just cracked the windows wide open. You can put your hand right through," said L.A. Councilman Tom LaBonge. "(There's) severe damage, water damage, but it wasn't damaged physically to where it will be uninhabitable. There's just a lot of cleanup going on right now."
Anyone with business related to the affected city departments was asked to call 311 for information.
The City of Los Angeles Department of Aging, which provides community-based services, said 2,000 holiday gifts for local seniors are a "total loss." The Department was to remain closed until further notice, according to its website. One person who has offered to help the group is Clint Carlton with The Dream Center. Their website is www.dreamcenter.org.
The 1.3-million-square-foot Da Vinci apartment building had been under construction for several months. There was about $10 million in damage related to the apartment building alone, according to a preliminary estimate on Monday.
"We would like to thank the men and women of the Los Angeles Fire Department for their bravery, swift actions, and effective response in putting out the fire," developer Geoff Palmer said in a statement to Eyewitness News. "Though we have temporarily lost Building B, we will be opening Building A across the street at the end of January to those families looking forward to occupying their new homes."
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The 110 Freeway was initially closed in both directions, but the southbound side reopened just before 5 a.m. and three northbound lanes reopened around 10:15 a.m. The northbound side was fully closed at one point because of possible collapse of debris onto the freeway. The Temple, Broadway and Los Angeles off-ramps from the 101 Freeway were also closed.
As crews were fighting the fire in downtown, another blaze erupted about eight blocks away at a commercial building in Westlake District.
Officials say there's no information at this time to indicate that the two fires are related.
Anyone with information about the fires was asked to call (213) 893-9850.
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