Federal land management agencies are being asked to make more employees available to fight wildfires because crews and equipment have been stretched to the limit by nearly 60 major blazes around the West.

For the first time since 2003, the National Interagency Fire Center over the weekend raised its response status to the highest threat level, a move triggered when nearly all available crews and firefighting resources are committed.

The move allows federal firefighting coordinators to summon additional federal employees, military reinforcements and foreign fire crews if necessary.

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"It frees up what we call the militia — agency employees whose regular job may be as a biologist or realty specialist but who are trained in fire duty and can now be called up to help," said Randy Eardley, a U.S. Bureau of Land Management spokesman at the federal firefighting center in Boise.

More than 24,000 firefighters were working on fires across the West on Monday, including 58 large fires of 500 acres or more.

The biggest active fire in the country was in northern Nevada, where nearly 300 square miles of grass and sagebrush had burned. It was 10 percent contained Monday, and fire bosses had no estimate when it would be surrounded.

No homes were in immediate danger, though one outbuilding had been destroyed, said Jamie Thompson of the U.S. Bureau of Land Management in Winnemucca, Nev.

More people were told to evacuate Monday from areas south of Chadron, Neb., on the fourth day of fires that have scorched nearly 80 square miles.

About 45 to 50 people were affected by the latest evacuation orders, and hundreds of others evacuated over the weekend were kept from their homes.

Four rural houses have been destroyed and several more damaged since lightning sparked the fires last week.

In Montana, more firefighters, equipment and aircraft arrived Monday as crews fought to corral a fire that blew up rapidly in Glacier National Park over the weekend, fanned by strong winds and blistering heat.

Firefighters got some relief Monday with calmer winds and lower temperatures, but officials said the fire — estimated at 34 square miles — still posed a threat to the gateway community of St. Mary.

The blaze came within a mile of the town over the weekend. The National Park Service on Sunday evacuated its administrative site there, as well as several area campgrounds.

Most of the park remained open to visitors, officials said.

Residents of a subdivision in central Oregon were allowed to return late Monday as crews tamed a fire there, though evacuation orders remained in effect for another 500 residents of two subdivisions near the tourist town of Sisters.

The subdivisions appear to be protected from the 14-square mile fire, which is 30 percent contained, said Scott Brayton, a fire spokesman.

An evacuation order was also lifted for several dozen residents near Weaverville in northern California after a wildfire that destroyed one home calmed down.

In Idaho, a 5-square-mile fire in the mountains fed on bug-killed evergreen stands as it neared a cluster of vacation homes and a mining museum.

More than 70,600 timber and range fires have burned on federal land so far this year, higher than the 10-year average of 50,984, according to the National Interagency Fire Center. Because of unusually large early-season range fires in Texas and Oklahoma, the acreage burned so far in 2006 is 5.5 million, compared with a 10-year average of 3 million acres for the same period.