Dubbed the Ponderosa Fire, the lightning-sparked blaze roared through brush and heavy timber in Tehama and Shasta counties, about 125 miles (200 km) north of the state capital Sacramento, since it started on Saturday.

Firefighters were finally able to survey the damage from the air in one of the more heavily populated areas affected, to the southeast of tiny Manton, on Tuesday.

The structures destroyed include not only residential houses but also barns and sheds, but firefighters were not expected to inspect the damage up close and on foot until Wednesday, Chico Fire Division Chief Shane Lauderdale told Reuters.

"There is a good chance that number (of destroyed buildings) will go up, because they haven't been able to get into the whole area affected by the fire," Mike Witesman, a spokesman for the California Department of Forestry and Fire Protection, said.

More than 2,000 fire personnel successfully fought strong winds all day Tuesday to save the neighboring small town of Shingletown from burning, Lauderdale said.

However, more than 200 residences remain threatened by the blaze burning over steep and rugged rural terrain.

Two firefighters have suffered minor injuries while fighting the blaze, which officials said has been 40 percent contained.

The Northern California fire is among nearly three dozen large conflagrations burning out of control through the drought-stricken Western states, devouring well over 1 million acres, according to the National Interagency Fire Center in Boise. (Reporting by Mary Slosson; Editing by Bill Trott, Lisa Shumaker and Pravin Char)

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