Gusting winds and high temperatures hampered firefighters on Sunday as they battled to tame a record wildfire in northern Colorado that has charred more than 85 square miles (200 square km) and sent a plume of smoke billowing thousands of feet into the air.

The winds and smoke also grounded air support for firefighters battling the so-called High Park Fire raging for more than a week in mountain canyons 15 miles west of Fort Collins, fire spokesman Brett Haverstick said.

The lightning-sparked blaze has destroyed 181 homes since it was reported June 9, ranking it as the most destructive wildfire on record in Colorado.

It is also blamed for the death of a 62-year-old grandmother whose remains were found in the ashes of a mountain cabin where she lived alone.