(AP) -- ROCKY MOUNTAIN NATIONAL PARK, Colo. (AP) Firefighters have built more containment lines around a fire burning in Rocky Mountain National Park.

The 911-acre fire was 60 percent contained Thursday. Fire managers say crews have been working long hours in steep, rugged terrain and have been spending nights camped out in the mountains.

In southern Colorado, a fire that started on the Great Sand Dunes National Park has grown by 401 acres, but that's by design. Firefighters have been burning out land between fire lines and the fire's edge to reinforce the containment line.

That fire is now listed at 6,208 acres.

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