Wind-driven wildfires swept across Boulder County grasslands, destroying at least four structures and prompting mandatory evacuations of at least 500 homes, county spokeswoman Barbara Halpin said. Sheriff's Cmdr. Phil West said two firefighters suffered minor injuries.
The fires started in parched, rolling grasslands dotted with homes and horse ranches about 25 miles northwest of Denver. West said the fire apparently started when wind knocked down a power line.