L.A. fire, ruled arson, is now a crime scene

Eyewitness accounts and incendiary material point to arson as the cause of the largest fire in the area's history.

Now the dirty work begins.

With the deadly wildfire that has burned 150,000 acres now gone from its point of origin, homicide detectives and arson investigators are poring over the evidence left behind for clues leading to the person or persons responsible.

The US Forest Service determined Thursday that the blaze was started intentionally – making the deaths of two firefighters homicides. They have as yet announced no suspects and are not releasing the precise coordinates. But it is an area that is not currently burning, although investigators said the fire passed back over what is now an official crime scene.

"After a forensic examination at the point of origin, arson investigators have concluded that the Station Fire was the result of an act of arson," said Rita Wears, US Forest Service commander.

Investigators are focusing on an area north of Los Angeles as the possible epicenter of the fire, which has burned for about 10 days.

"It's a very difficult investigation," says Tom Debellis, an information officer with the City of Colton Fire Department, one of many local fire agencies participating in this interagency effort. That's because fire has passed over the point of origin twice, he says, igniting light grasses the first time and more dense wood after the fire built up strength.

The fire has been officially designated the largest in Los Angeles County history, says Matt Levesque, inspector for the L.A. County Fire Department. So far, this fire has claimed the lives of two firefighters and burned 70 structures.

Officials say the blaze is now 42 percent contained. By Thursday, safety officials had lifted all evacuation orders for residential areas, allowing people to return to their homes.

Mr. Levesque says the arson investigators caught a break because even though the fire shot up into the thousands of degrees (hot enough to melt automobiles), it was not exacerbated by the usual Santa Ana winds – the hot, dry breezes that traditionally sweep in this time of year from the Sierra Nevadas. That's important because the investigators are searching for fire patterns.

It was both eyewitness accounts and incendiary material that led the US Forest Service to determine that the fire was set on purpose, although officials have declined to offer more details.

"That's because this is an ongoing investigation," says Marian Swinney, with the L.A. County Fire Department, stationed at the main Hansen Park Dam command post.

Making details public could damage attempts to find and prosecute suspected arsonists, Lee Baca, Los Angeles County sheriff, told the Los Angeles Times.

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