Fires stretch US to limit

Recent weather has produced tinderbox conditions

The United States says it may ask other countries for help in fighting dozens of wildfires currently raging across 11 western states.

Some 20,000 civilian and military personnel from across the US and Canada are battling nearly 50 massive blazes - the worst for more than a decade - which have destroyed vast areas of land and darkened the skies with smoke.

Many fire crews are nearing exhaustion

"Firefighting resources are stretched thin," Undersecretary for Natural Resources and Environment Jim Lyons told reporters on Wednesday.

He said both Mexico and Australia had already been alerted that they could be asked to join Canada in providing assistance.

The US federal government is spending $15m a day - a total of $300m to date - to support efforts to contain the fires, with new blazes breaking out every day.

Firefighting resources are stretched thin... We may be requesting resources from other countries

Environment Undersecretary Jim Lyons

Teams battling the fires have at their disposal 700 fire engines, 150 aircraft and two military battalions - but this is proving to be insufficient.

"From Australia, we're likely to seek additional overhead [support] - that is, people with operations and logistics experience.

"In Mexico we may seek additional firefighting crews to work on fires in the southwest so we can rest crews," Mr Lyons said.

Tinderbox conditions

Deputy Agriculture Secretary Richard Rominger said nearly 3.5m acres (1.5m hectares) of land had been scorched in the last few weeks, a figure nearly matching the annual average.

"Unfortunately, conditions are expected to get worse before they get better," Mr Rominger said.

August is traditionally the worst month for wildfires, which are a natural part of the ecosystems of the western US. The current combination in the area of high temperatures, low humidity and lightning unaccompanied by rain create perfect conditions for them.

Dry lightning overnight on Tuesday to Wednesday sparked hundreds of new fires, including 17 major blazes in California, Utah, Montana and Nevada. Fires are also raging in Colorado, Arizona, Idaho, New Mexico, Texas, Washington and Wyoming.

The fires have been blamed for at least five civilian deaths, and have forced the evacuations of hundreds of people from their homes.

No let-up in sight

In one of the worst-affected states, California, four firefighters suffered second-degree burns on Wednesday, but big gains were made against a giant fire in the southern Sierra Nevada and a forest fire on the central coast was surrounded.

Hundreds have been evacuated and their property destroyed

California's biggest blaze, which had burned more than 70,000 acres in the Sequoia National Forest, was now 40% percent contained, officials said.

Forecasters say the kind of break in the weather needed to change the west's tinderbox conditions may not occur until October.