Several grass fires have forced thousands of people to flee their homes in two Colorado cities as high winds knocked down powerlines in Boulder, causing the massive blazes.
The National Weather Service said a gusting wind of 110 mph was reported n the Boulder area between Highway 93 and Colorado 72 at around 11:30 a.m.
The agency called it a "life-threatening" situation.
USA Today reported that 13,000 residents in Superior were ordered to evacuate because of a fire spread northwest of town.
Superior Mayor Clint Folsom told KMGH that more than 200 structures, including residences, were likely destroyed by the wildfire.
The Boulder County sheriff told news outlet reported that the Marshall Fire had destroyed more than 500 structures by Thursday.
The news organization reported that Colorado Gov. Jared Polis activated the National Guard and approved federal assistance to help people impacted by the wildfires devastating Boulder County.
According to the Associated Press, 21,000 residents in Louisville were also evacuated because of the wildfire.
A spokesperson for UCHealth Broomfield Hospital told the AP that six people were injured in the fires and were being treated at the facility.
Boulder County Sheriff Joe Pelle said during a press conference that about 580 homes have been burned in the fire, including 370 in Superior and 210 in Old Town, KMGH reported.
The news outlet reported that portions of U.S. Highway 36 were also shut down because of the blaze.
KMGH reported that the Boulder Police Department had ordered drivers to stay off the roads as the smoke makes it hard to see.
The news station reported that due to a power outage at the South Boulder Recreation Center, the replacement evacuation center had been relocated to the North Boulder Recreation Center.