With dozens of homes and cabins already destroyed by wildfire, crews worked Sunday to protect hundreds of others on the scenic Kenai Peninsula.
The fire has burgeoned to 81 square miles (210 sq. kilometers) since Tuesday, consuming 35 far-flung cabins in the Caribou Hills, state fire information officials said. Forty other structures, including sheds and outhouses, were also lost in the popular hunting and snowmobiling area about 80 miles (129 kilometers) south of Anchorage.
The blaze is carving easily through wide swaths of spruce killed by beetles, and crews are finding it hard to maneuver in the warren of footpaths and gravel roads crisscrossing the hills, said fire information officer Elaine Hall.
The fire threatens another 600 residences and cabins, Hall said. An evacuation order has been in effect since Friday, but fire officials said an unknown number of residents have refused to budge.
"Some folks stayed to protect their houses when they were supposed to evacuate, but we haven't heard about anyone being hurt so far," said Bob Evenson, a fire volunteer.
Crews were trying to take advantage of light rain early Sunday, building a series of fire breaks on the western and northwestern flanks of the fire. Hot, dry weather with winds up to 20 mph (32 kilometer) is expected to fan the flames Monday.
Many of the homes in the area are used only seasonally.
Nearly 400 firefighting personnel from around Alaska and the lower 48 states have arrived throughout the week, according to the Alaska Interagency Management Team.
The blaze began when sparks from a grinder used to sharpen a shovel fell into dry grass.
Smaller fires are also burning in the Mat-Su Valley a few dozen miles (kilometers) north of Anchorage.
Alaska's fire season is just getting started. The worst recorded season was 2004, when fires consumed a total of 6.6 million acres (2.67 million hectares), or 10,312 square miles (26708 sq. kilometers).
In Montana, higher humidity and a change in fuels slowed the progress of a wildfire in the Lewis and Clark National Forest. It moved from heavy timber into a brushier area and continued to burn away from six structures, a mix of commercial property and vacation homes, fire officials said. The fire was not contained.