Firefighters have contained a wildfire that broke out Wednesday in Walla Walla County and was spread by winds across more than 30 square miles of grassland.

The county emergency management department says firefighters are mopping up Thursday.

The department says the fire burned some abandoned structures of no value. It also burned nine power poles that caused a local electrical outage.

More than 100 firefighters from the county's eight fire districts and cities in southeast Washington battled the blaze.