A fast-moving grass fire that started at a landfill destroyed an unknown number of homes and other buildings and forced hundreds of people to evacuate from a rural area in Wyoming.

No injuries were reported but at least 10 homes and several outbuildings were damaged. Some of those were destroyed. An evacuation center was set up at Casper College.

Winds topping 50 mph Sunday afternoon pushed the fire onto the grassland from a composting area at a landfill about a mile from Evansville. The flames spread into a thinly populated area and a rural subdivision, Natrona County Fire Marshall Bob Fawcett said.

"The winds were the biggest factor in it getting out of control and away from that area," Fawcett said Monday.

Flames resumed spreading after the wind picked back up Monday afternoon. Police, who had allowed some evacuees to return under escort to check on livestock and other animals, kept the evacuation order in place.

Fawcett estimated the fire burned several thousand acres. Firefighters were still assessing the damage, including how many structures burned, Fawcett said.

More than 100 firefighters and two air tankers were fighting the fire and at least a couple hundred people had to evacuate from the area.

The cause of the fire at the composting area Saturday evening remained unknown.