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Massive Da Vinci fire in downtown L.A. was arson, investigators say

Investigators conclude massive downtown L.A. fire was arson

Federal investigators have concluded the fire last week that consumed a downtown Los Angeles apartment complex under construction was deliberately set, according to a source close to the investigation.

Investigators have been digging through the rubble left by last week's blaze, sometimes wading in knee-deep rainwater during the storms that swept through the area, collecting samples from suspected points of origin. A national response team with the Bureau of Alcohol, Tobacco, Firearms and Explosives was called to assist in investigating the scene because of the magnitude of the fire.

The blaze, which broke out in the middle of the night, all but obliterated a seven-story building of the Da Vinci apartment complex and caused extensive damage to the adjacent 110 Freeway and city buildings. It took 250 firefighters an hour and half to put out the flames that rose to heights taller than many downtown buildings. The total damage was estimated to be in the tens of millions of dollars.

Fire officials said previously that they suspected arson because of how quickly the building appeared to be engulfed. Even though a fire station was a few hundred yards away, two-thirds of the building was already burning by the time firefighters received the initial report at 1:09 a.m. and rushed over, Los Angeles City Fire Chief Ralph Terrazas said.

The ATF national response team, at the end of its investigation, reaches one of three conclusions – incendiary, accidental, or undetermined. Given Thursday’s conclusion that the fire was determined to be "incendiary," or deliberately set, local authorities will probably launch an arson investigation to identify those responsible for the blaze.

Earlier this week, authorities announced that they were looking for two potential witnesses who were present at or near the scene of the fire. One man is seen in a surveillance video calmly walking down the street before the start of the fire. The second was captured on freelance news footage after the fire is in full force appearing to attempt to get through a construction fence into the burning building. As of Thursday, investigators had yet to identify the men.

Authorities said they were not suspects or persons of interest, but "purely someone we are seeking to interview as an investigative lead."

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