LOS ANGELES (AP) - Fire bosses declared progress early Friday in taming the 226-square-mile arson fire north of Los Angeles that has led to a homicide investigation into the deaths of two firefighters.
Flames had died down early Friday and the blaze, which was 42 percent surrounded, was "pretty quiet," fire spokesman John Huschke said.
Firefighters were using bulldozers to clear a containment line around the fire, which destroyed 64 homes and burned three people.
The fire has charred 148,258 acres of the Angeles National Forest, where many city residents escape to nature during the summer.
Investigators determined on Thursday that the 11-day-old blaze was arson, and Los Angeles County sheriff's homicide detectives were investigating.
Two firefighters were killed Sunday when their truck plunged 800 feet down a steep mountain road.
Incendiary material was found along Angeles Crest Highway, the Los Angeles Times reported Friday, citing an unidentified source close to the investigation. The massive blaze is thought to have started in the area.
Sheriff Lee Baca said details were being withheld to avoid jeopardizing the hunt for the arsonist.
County Deputy Fire Chief Mike Bryant said he was glad investigators were making progress in the probe, but "it doesn't mend my broken heart."
"Those were two great men that died," he said. "We've got to put this fire out so no one else gets hurt."
"When you find out it is intentionally set, it's hard to take. A death is a death, but it's so senseless when it's deliberately set," Huschke said.
A tribute for the two fallen firefighters was held before dawn Friday at the camp. Hundreds of firefighters took off their caps and helmets and bowed their heads as the men were remembered with speeches and a moment of silence.
Elsewhere, a 25-acre wildfire broke out just after midnight about 60 miles southeast in Orange County in the Cleveland National Forest, county fire Capt. Greg McKeown said. No homes were threatened.
On Thursday, a six-member firefighting crew mopping up in Angeles National Forest was overcome by fumes, apparently from the smoldering remains of a makeshift methamphetamine lab. Huschke said a hazardous materials squad was called in and one firefighter was hospitalized overnight.
Hand crews and water-dropping helicopters had almost contained the fire's western flank in rugged canyons, but 65 miles of fire line have yet to be cut, U.S. Forest Service Incident Commander Mike Dietrich said.
A historic observatory and TV, radio and other antennas on Mount Wilson, which at one point was dangerously close to the flames, were "looking pretty darn good," he said, but the fire was pushing east into the wilderness and down toward foothill cities of Monrovia, Sierra Madre and Pasadena.
Even in a landscape blackened by wildfire, clues abound for investigators following the path of a blaze and trying to find out how it started. Investigators start where firefighters were first called and work backward.
Jeff Tunnell, a wildfire investigator for the Bureau of Land Management, said even in charred terrain, investigators can detect important signs in the soot.
"Fire creates evidence as well as destroys it," said Tunnell, a veteran of 50 wildfires who is based in Ukiah. "We can follow fire progression back to the point at which it started."
Clues can come from burned trees and grasses, where the amount of burned foliage can show the direction and speed a fire was moving. Investigators search for the remains of whatever started the fire: a charred match or cigarette butt, a piece of metal from a car or part of a power cable. If no such object is found, they often conclude that a fire was "hot set," meaning it was started by a person holding a lighter to the brush.
"That's what you are going to assume, because there's no other competent ignition source," he said.
Most wildfires are caused by human activity. Even a fire caused by a singed squirrel tumbling from an electrical transformer is designated as human-caused, because humans put the electric box there, Tunnell said. Other wildfire causes are lightning and volcanoes.
At the time the current fire broke out, Forest Service officials said there was no lightning and there were no power lines nearby.
Three years ago, arson investigators probing the cause of a wildfire in the San Jacinto Mountains that killed five firefighters discovered evidence of different types of incendiary devices at several fires. They recovered everything from simple paper matches to more elaborate devices made up of wooden matches grouped around a cigarette and secured with duct tape or a rubber band.
The evidence was enough to build a first-degree murder case against mechanic Raymond Lee Oyler. In March, the evidence was used to convict him and send him to death row.