Thousands of homes are under evacuation orders as a human-caused fire that sparked in Parleys Canyon Saturday afternoon continues to spread quickly near I-80.

Summit County Sheriff Martinez tweeted that residents of Summit Park and neighboring Pinebrook subdivision are a part of mandatory evacuations as the fire continues to grow. Lambs Canyon and Millcreek Canyon were also under evacuation, according to Utah Fire Info, which is composed of state and federal firefighting agencies.

The sheriff said some residents have refused to leave, which he said is "hampering efforts and are putting first responders in danger."

"PLEASE evacuate immediately!" he tweeted.

In all, Utah Fire Info estimated that 6,000 to 8,000 homes are under evacuation. Those being evacuated are being told to go to an emergency shelter at Park City High School, located at 1750 Kearns Blvd. Park City. Park City Fire District officials said dispatchers were planning on sending a reverse 911 call to residents in the area. Their firefighters had been reassigned from the fire to "structure protection" in the Summit Park area.

Red Cross officials said in a statement that evacuation residents are required to wear masks inside the evacuation center regardless of vaccination status "to ensure the safety of our workforce and those we serve."

Gov. Spencer Cox tweeted that his office was monitoring the fire "closely."

The blaze, dubbed the Parleys Canyon Fire, was first reported shortly after 1:15 p.m., according to the Utah Highway Patrol. Firefighters said a vehicle's "poor working" catalytic convertor tossed hot particles along the roadside, sparking the fire.

A caller told dispatchers there were two grass fires near each other not far from Lamb's Canyon. The two fires were about a mile apart and flames quickly shot up the mountainside, away from I-80 with the help of east-blowing winds, Utah Department of Public Safety officials said.

Utah Fire Info reported the fire had grown to 2,500 to 3,000 acres by 4:30 p.m. It remains 0% contained.

Nancy Eagan, a resident of Summit Park area, told KSL-TV that a friend who could see Lamb's Canyon from his home sent her family of the fire, which is when she first learned about it.

"It just seemed like it moved so fast. There was so much orange smoke we could see from our house and found out right away we needed to get packing and getting ready to leave," she said. "We grabbed just clothes and some bathroom items and valuables and packed both of our vehicles. It's nerve-wracking, definitely. ... It's been close so it's scary."

The Northern Utah Type 3 team was called to the fire along with more than a dozen ground and air vehicles from local, state and federal departments, according to Utah Fire Info.

The fire also has severe impacts on traffic in the area. Utah Fire Info and multiple fire agencies reported that I-80 was closed in both directions; however, the Utah Department of Transportation reports one lane was open for eastbound traffic and UHP tweeted that westbound I-80 is open. UDOT tweeted that the fire was causing "significant delays" on I-80.

"Avoid the area and use an alternate route," the agency tweeted.

At the same time, Rocky Mountain Power officials said there are close to 2,500 homes in the Park City area without power as a result of the fire. UDOT also reported traffic signal issues tied to widespread power outages east of Kimball Junction in the area.

This story will be updated as soon as more information is made available.