Officials say the Mosquito Fire in California is now the state's largest wildfire this year, having burned more than 64,000 acres since it ignited on Sept. 6.
As of Thursday, the blaze had destroyed 70 structures and damaged 10 in El Dorado and Placer counties and was only 20% contained, according to the California Department of Forestry and Fire Protection (Cal Fire).
More than 9,200 structures were threatened, Cal Fire said.
USA Today and ABC News reported that it became the largest wildfire in the state when it exploded by more than 15,000 acres on Monday, surpassing the McKinney Fire, which has burned more than 60,000 acres in Siskiyou County and is currently 99% contained.
Cal Fire said evacuation orders are in effect in several towns including Michigan Bluff, Volcanoville, and Quintette as of Thursday afternoon.
USA Today reported that smoke from the wildfire has created unhealthy air quality in the area as well as in Nevada.