DENVER - Firefighters grappling with the two most destructive wildfires on record in Colorado reported progress on Monday, but were steeling themselves for a long season in what has already been a dangerously active fire year in the western United States.

The fires, which left a haze of smoke over the state's urban corridors, have displaced tens of thousands of people and left vast swathes of forest a blackened wasteland in addition to charring more than 600 homes.

"I don't think we've seen a fire season like this in the history of Colorado," Governor John Hickenlooper said last week after surveying the destruction wrought by the deadly Waldo Canyon Fire west of Colorado Springs.

The wind-driven Waldo, which is blamed for two deaths and the destruction of 346 homes, was now 55 percent contained, incident commander Rich Harvey said on Monday.

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