Hot winds blowing up to 60 mph drove brushfires across firebreaks Thursday, threatening a foothill community of 90,000 people.

By daybreak, the two separate brushfires in the San Bernardino Mountain foothills had blackened 6,000 acres, destroying at least one house and prompting the evacuation of a high school and a juvenile detention facility, officials said.Fifteen homes high in the canyons 40 miles east of Los Angeles were evacuated Wednesday night. Early Thursday, officials began evacuating a suburban neighborhood in the north end of Rancho Cucamonga, a city of 90,000 people north of Fontana.

"The fire is trying to go right into the community," said California Department of Forestry spokeswoman Holly Kress.