More than 32,000 people have fled their homes in the US state of Colorado as a growing wildfire breached perimeter lines and moved into the city of Colorado Springs.
Traffic and smoke choked the streets as people hurried to evacuate the city and a nearby Air Force Academy.
Over 800 firefighters are battling a fire that has scorched over 6,200 acres (2,509 hectares) and is 5% contained.
Extreme fire warnings are in place across several western US states.
The Waldo Canyon Fire began on Saturday but quickly became the top national priority for firefighters as winds of up to 65mph (104km/h) sent the flames surging towards Colorado Springs.
"It was like looking at the worst movie set you could imagine," Colorado Governor John Hickenlooper said after surveying the fire from the air on Tuesday.
"It's almost surreal. You look at that, and it's like nothing I've seen before."
Heavy ash and smoke was billowing from the hillsides west of Colorado Springs and southbound traffic was temporarily closed on the Interstate 25 motorway, which runs through the town.
The city is Colorado's second largest, situated just off the main north-south highway.
Elsewhere in Colorado, the High Park fire in the west of the state has been burning for weeks and remains just 45% contained, although fewer homes are under imminent threat.
Fires or fire warnings are also in place in Montana, Utah and Wyoming, just weeks into the annual wildfire season.
Dry, hot temperatures are expected to continue across much of the US this week, with little rain forecast to dampen the blazes.