Two killed fighting California fires

At least one structure was consumed by the blaze.

CASTAIC, California (CNN) -- Two pilots died fighting a fast-moving fire in Mendocino County, California, Monday when their air tankers collided.

The aircraft were fighting a 200-acre blaze near Ukiah, a forestry official told The Associated Press.

"They were crossing paths to each other," witness Jeff Anderson told KRON-TV in San Francisco. "It looked like one might have knocked the tail off the other one."

All other firefighting aircraft were grounded following the collision.

VIDEO CNN's Thelma Gutierrez reports on a sudden outburst of wildfires that threatens homes in north Los Angeles County, California (August 27) Play video (QuickTime, Real or Windows Media)

Meanwhile, another rapid fire threatened homes and other residential property in northern Los Angeles County Monday with flames leaping hundreds of feet into the air and thick, gray smoke billowing into the sky.

At least one structure was consumed by the blaze. There were no immediate reports of injuries.

"The fire is currently burning out of control," said Ed Martinez, a spokesman with the Los Angeles County Fire Department.

More than 200 firefighters were on the ground, most placed around threatened homes in the area. Four helicopters also were participating in the firefighting efforts.

The fire was fanned by winds of about 10 mph and had burned about 200 acres through thick, dry brush in rugged terrain. It had burned 150 acres in less than an hour.

"The flames are intense. [Firefighters] are doing the best they can to protect property, putting themselves in extreme danger. The winds and the terrain are making things worse," Martinez said.

He added, "You have some beautiful homes up in that area."

Martinez urged anyone in their homes to remain inside until fire crews can get there. Many of the roads in the area are just big enough for one car and Martinez said if people clog the roads it could "hamper firefighting efforts."

The cause of the fire was not immediately known. It began around 12:45 p.m. and could not have come at a worse time for firefighters.

"This is actually the perfect time of day for the winds and the heat to line up to make firefighting at its worst," Martinez said.

"Fires at this time of day normally will be assisted in burning by the heat, the overhead sun, the temperature and winds in that area. Until it gets later on in the day, the firefighters are going to have their hands full."