Firefighters on Sunday were battling wildfires that spread quickly in parched forests in Colorado and New Mexico, forcing hundreds of people from their homes and the evacuation of wolves from a sanctuary.

The Colorado fire, in a mountainous area about 15 miles west of Fort Collins, grew to 31 square miles within about a day of being reported, destroying or damaging 18 structures.

In southern New Mexico, strong winds grounded aircraft fighting a 40-square-mile wildfire near the mountain community of Ruidoso. Crews were working to build a fire line around the blaze, which started Friday and has damaged or destroyed 36 structures.

It wasn't immediately clear how many of the lost structures were homes.