Towering walls of smoke and flame closed in on the town of Show Low in Arizona today as firefighters fought to keep the largest wildfire in the state's history from incinerating hundreds of additional houses.
Fire officials reported some progress in slowing the blaze after bulldozer teams struggled through the night to cut a last-ditch fire break.
But they said the mountain town of Show Low was still in grave peril as the monster fire - which covers 305,000 acres and has destroyed 185 houses in eastern Arizona - edges closer.
"A tremendous risk of fire coming into Show Low on the northwest edge of town still exists," said Mr Jim Paxon, spokesman for the fire management team.
Show Low, whose 8,000 residents were told to leave on Saturday, remained a ghost town with police patrolling the deserted streets and fire and emergency vehicles the only traffic on the roads.
Teams of firefighters staked out positions throughout the town, ready to spring into action in case floating embers from the nearby blaze should spark fresh fires.
About 2,200 people are waging war against the fire, attacking the behemoth blaze with about a dozen helicopters and 15 air tankers used to drop flame retardant.
The Federal Aviation Administration opened a temporary air traffic control center in Show Low to direct the air operation, one of the largest ever mounted in the state.
The Arizona fire now measures some 480 square miles, an area roughly as large as the city of Los Angeles.
Fire officials said today that weather conditions remained favorable with little wind and moderate temperatures.
An estimated 30,000 people have been evacuated from their homes.