NASA image shows California wildfire smoke as far as Utah

Smoke from the wildfires in Northern California has spread as far as Utah, satellite images from NASA show.

The flames have been engulfing Northern California for several days, claiming the lives of six people and destroying homes across the region.

Firefighters are hoping the calmer winds will help them make more progress as they carve out buffers to contain the fires.

A NASA statement explained: "NASA's Aqua satellite captured this natural colour image of the fires in California and the resultant smoke that has shrouded the state and swept eastward as far as Salt Lake City and still moving."

More than 880 homes and 300 other buildings have been reduced to ash, and 3,600 firefighters, some drafted in from other states, are tackling the two separate fires.

The town of Redding has been almost completely evacuated, with 37,000 people fleeing their homes.

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On Monday, firefighters said they had made some progress, carving out buffer lines in 23% of the fire's perimeter.

This wildfire has become the seventh most destructive in California's history. It was whipped up by gale force winds, turning into a firestorm which has jumped the Sacramento river.

It has now burnt 172 square miles (445 kmsq) of the northern Californian region.

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Two firefighters are among the dead, as well as two young children and their great-grandmother. They died while huddling under a wet blanket.

Across the West of the US, wildfires have scorched about 4.6m acres of land.

California fire officials said fires within the state have burnt 410,000 acres since January, the highest year-to-date total for the end of July in 10 years.