PIÑON CANYON MANEUVER SITE, Colo. -- Firefighters are still battling a wildfire at the Piñon Canyon Maneuver Site in southeastern Colorado, which officials said grew to more than 43,000 acres Sunday.

As of Sunday morning, the fire was 33 percent contained, firefighters said.

"Local and county fire resources have cooperated well with state, federal and Army resources during the entire incident," said C.K. Morey, district forester for La Veta district of the Colorado Forest Service.

Low humidity and shifting winds will test fire lines Sunday afternoon, but a forecasted increase in humidity and lower temperatures should help firefighters contain the blaze.

Seven aircraft, three water tenders and 19 engines are currently working the fire.

Lightning is believed to have started the fire last Sunday on the Army's Piñon Canyon Maneuver Site. It spread to surrounding ranch land as well as state and federal land later in the week.

Residents Oppose Army Expansion At Site

For the past two years, the Army has been trying to nearly triple the size of Fort Carson's maneuver site, from 368 square miles to more than 1,000 square miles. It's a move that has been fiercely opposed by most ranchers in the area. Some of them say the wildfire highlights problems with the way the Army operates the site.

Las Animas County Commissioner Gary Hill said the fire wouldn't have spread so quickly if the Army had allowed cattle to graze on the current 238,000-acre site.

"Wouldn't it make more sense to have ranchers paying grazing fees to the government to let their cattle on the land, instead of taxpayers having to pay firefighters to put out a wildfire?" asked Hill, whose ranch is in the Army's expansion area.

Lon Robertson, a rancher leading one of the groups opposed to the expansion, said the fire would have been stopped sooner if it had started on private land. He said expanding the land the Army controls and allowing live-fire exercises on it would increase the risk of wildfires that could again spread to surrounding ranches.