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Los Angeles fire officials and a representative for a team of federal agents on Wednesday said the huge blaze that ripped through the unfinished Da Vinci apartment complex downtown earlier this week was not yet being treated as criminal, but dozens of arson investigators were working the case.

A 526-unit apartment complex in downtown L.A. caught fire on Dec. 8, 2014. (Credit: Eric Spillman/ KTLA)
A 526-unit apartment complex in downtown L.A. caught fire on Dec. 8, 2014. (Credit: Eric Spillman/ KTLA)

Agents from the federal Bureau of Alcohol, Tobacco, Firearms and Explosives arrived Tuesday evening and began working early Wednesday alongside investigators from the Los Angeles Fire Department to determine the cause of the fire, which erupted at the seven-story, 526-unit building Monday in the early morning hours.

Some 50 federal agents were working on the case, authorities said at a late morning news conference Wednesday.

“The people who are going to be investigating this fire are some of the best fire investigators in the world,” said Carlos Canino, ATF field special agent. “Any time you have a building under construction the size of a city block that goes up, it has some significance.”

The fire had not yet been deemed “criminal,” but nothing was being ruled out, authorities said.

Fire Chief Ralph M. Terrazas used the news conference to remind Angelenos that “arson is a very serious crime and we have zero tolerance for it.”

An accelerant-detection K-9 stood with federal and  local investigators at a news conference Dec. 10, 2014. (Credit: KTLA)
An accelerant-detection K-9 stood with federal and local investigators at a news conference Dec. 10, 2014. (Credit: KTLA)

The building, located right off of the four-level interchange of the 110 and 101 freeways, was nearly leveled as a result of the massive fire. Flames towered dozens of feet above the burning structure and were visible for miles around the city, as were thick plumes of dark-colored smoke.

The Fire Department was first alerted to the blaze by a passerby who called 911, officials said Wednesday.

The building has round-the-clock security, but it’s not clear where the guard was when the blaze broke out, fire spokesman David Ortiz said Tuesday. Investigators will be trying to determine where the guard was, Ortiz said.

Given the scope of the damage and the number of witnesses that will need to be interviewed, the investigation could take weeks or months, authorities said.

Safety officers were walking through the wreckage Wednesday to ensure agents could enter to begin examining the vast amount of evidence inside, officials said.

An ATF accelerant-detection K-9 named Major and his handler — referred to by Canino as the “gold standard” of law enforcement canine teams — planned to examine the structure for “ignitable liquids.”

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)

Roughly two-thirds of the under-construction apartment tower was destroyed as the blaze burned an area the size of a full city block. The building had approximately 1.3 million square feet of floor space.

As of Wednesday morning, several stairwells remained standing amid the charred building’s shell and debris where the fire had burned.

Two neighboring high-rises were damaged, including the 15-story Los Angeles County Health Services building.

The intense heat emitted from the blaze was also responsible for cracking more than 160 windows at the Los Angeles Department of Water and Power’s iconic John Ferraro Building.

Investigators walk alongside the smoldering ruins of a building that burned in downtown L.A. on Dec. 8, 2014. (Credit: KTLA)
Investigators walk alongside the smoldering ruins of a building that burned in downtown L.A. on Dec. 8, 2014. (Credit: KTLA)

One person was treated for smoke inhalation, but no other injuries were reported.

The blaze forced the 110 Freeway to be closed in downtown for hours, and the heavily trafficked roadway wasn’t fully reopened until the following morning. Temple Street was also closed but was expected to reopen Wednesday.

ATF agents were called in to assist with the investigation because of the extensive damage to the Da Vinci complex and the resulting potential for “significant monetary losses,” according to an LAFD news release.