Firefighters hosed down burned hills covered in ashes Monday, trying to prevent the wildfire that burned about 800 acres near West Hills on Sunday from sparking again, officials said.
"We are going to keep pouring water, just to make sure the fire is completely out," said Joe Luna, information officer for the Ventura County Fire Department. "We can't miss one spark. One spark is enough to ignite a fire."
Hundreds of firefighters and emergency crews from Los Angeles and Ventura counties battled thick black smoke Sunday afternoon for several hours before containing the blaze about 11 p.m., Luna said. Fire officials said a blaze is contained when it is kept from spreading and reaching people or homes, and it is controlled when the flames have been extinguished.
The cause of the fire remained under investigation Monday.
The fire broke out on the site of the planned Ahmanson Ranch development west of the Los Angeles County border and quickly spread northeast, burning mostly in Ventura County, near the Ventura Freeway and east of Las Virgenes Road.
"The fire started in an active area, where people hike," said Ray Rodriguez, a fire inspector for the Los Angeles County Fire Department. "It could have been caused by a number of things, a broken glass, cigarette butt, campfire."
Fire officials are asking residents who live near brushy areas to clear their property of all dry vegetation and be on the lookout for fires. Brush fires are most common from May through November, Luna said.
Sunday's fire was the largest in the San Fernando Valley so far this season and the first in Ventura County.
"We were fortunate that the fire did not hit any homes," Luna said. "It got pretty close at times, but nobody was injured."
On Sunday officials at the Ahmanson Land Co. were worried that the fire had destroyed the San Fernando Valley spineflower.
"But we were glad to find out the the fire did not affect either the spineflowers or the nearly extinct red-legged frogs," said Tim McGarry, spokesman for Ahmanson owner Washington Mutual. Developers came across the spineflower in May 1999 when most people thought the rare, spring-blooming species had become extinct, he said.
"As it gets hotter, we can expect to see more fires like this one," Luna said. "We just have to be real careful out there."