Federal ATF Agents to Join LAFD Investigation Into Huge Downtown L.A. Fire

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As firefighters continued to battle hot spots Tuesday, a multiagency investigation was underway into the cause of a massive blaze in downtown Los Angeles that ripped through an unfinished apartment complex and damaged at least three surrounding high-rise buildings.

A freeway sign is mangled in the aftermath of a huge fire in downtown Los Angeles on Dec. 8, 2014. Flames spread for a whole city block, nearly a million square feet, officials said. (Credit: ROBYN BECK/AFP/Getty Images)

A freeway sign is mangled in the aftermath of a huge fire in downtown Los Angeles on Dec. 8, 2014. Flames spread for a whole city block, nearly a million square feet, officials said. (Credit: ROBYN BECK/AFP/Getty Images)

Federal Bureau of Alcohol, Tobacco, Firearms and Explosives agents were expected to arrive Wednesday to begin working with L.A. city fire arson investigators to determine what caused the blaze, which started early Monday at a huge apartment building under construction near the four-level interchange of the 101 and 110 freeways.

"This has not been determined a crime scene, rather it is an investigative scene," said Los Angeles Fire Department spokesman Erik Scot in an emailed update late Tuesday morning. "After a thorough investigation, it will be determined if the fire was incendiary or accidental in cause."

Initial cost estimates predicted damage to the downtown area would be at least $10 million. California Department of Transportation officials estimated damage to the roadway, metal signs and fiber-optic cables underneath local freeways would cost about $1.5 million.

As the smell of smoke lingered in the downtown area, Caltrans crews worked throughout the night to remove rubble from the roadways. The 110 Freeway was fully reopened around 5:20 a.m.

The large blaze, initially reported around 1:20 a.m. Monday at 906 N. Fremont Ave. (map), was the first of three fires firefighters responded to in the L.A. area in less than three hours. No one was injured during the incidents.

Around 250 firefighters responded within minutes to a blaze at a seven-story, 526-unit building, part of the controversial Da Vinci complex, that consisted mostly of wood framing and was built against the 110 Freeway. The fire's towering flames and massive plumes of smoke could be seen from miles away.

Once the flames were extinguished, the building appeared to be almost completely leveled, two neighboring high-rises sustained fire damage and at least 160 windows at a third building -- LADWP's iconic John Ferraro Building -- were cracked as a result of the intense heat.

The Department of Aging, located at 221 N. Figueroa St. (map), was closed as a result of fire damage, and presents collected there for seniors were believed to have been destroyed.

Another damaged building, at 313 N. Figueroa St., was reopened Tuesday.

ATF agents were expected to begin working on their investigation Wednesday or Thursday, according to LAFD.

While firefighters continued to work to extinguish hot spots, a private company was contracted to help stabilize and demolish the burned structure.

A second fire broke out in Central L.A.’s Westlake area around 4 a.m. at a two-story building that was under renovation and housed businesses and tenants. It was believed to have been empty during the blaze.

A fire burned at a downtown L.A. apartment building on Monday, Dec. 8, 2014. (Credit: KTLA)

A fire burned at a downtown L.A. apartment building on Monday, Dec. 8, 2014. (Credit: KTLA)

About 100 firefighters worked to extinguish that fire when a third broke out about a mile from the first.

The third fire was “kept in check” and quickly put out, according to LAFD.

Investigators were to determine the cause of the fires as well as if the three incidents were related.

Fires “of this magnitude” are always treated as criminal, LAFD Capt. Jaime Moore told the Los Angeles Times Monday.

“We look at financial records; we’re going to look at activity in the area. They’ve already pulled at surveillance tapes, there’s a homeless encampment that’s nearby, they’ve spoken to individuals,” Moore said.

LAFD Deputy Chief Joseph Castro said that any theories on the cause would be “purely speculation” until a lengthy investigation is complete.

Anyone with information about how the fires started was asked to call the LAFD Arson Section at 213-893-9850.

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