The wildland fires in Lake and Colusa counties were declared 100 percent contained as of 7 a.m. this morning, Cal Fire officials said.

The Wye and Walker fires, which started Sunday, scorched through a total of 7,934 acres and destroyed two homes and an outbuilding and damaged two other residential structures, according to Suzie Blankenship, a fire prevention specialist for Cal Fire.

Officials said the two fires began minutes apart along rural Highway 20 in east Lake County and investigators are still searching for a cause.

The total cost of the fire was estimated at nearly $8.5 million, Blankenship said.

The worst of the fire burned on Sunday afternoon and into Monday morning, forcing evacuations from about 480 homes and businesses in Spring Valley, north of Highway 20 outside of Clearlake Oaks.

Some 1,100 firefighters battled the blaze at the peak of the fires, which burned across rugged dry brush and oak wildlands into Colusa County.

— Martin Espinoza and Randi Rossmann