“Firefighters worked late into the night to help secure the areas behind the homes in Daniel and secure portions of the fireline in Big Hollow canyon around the heel of the fire,” Wasatch County Fire confirmed in a post Friday on its official Facebook account.

The blaze burned more than 500 acres, with zero percent currently contained. It was reported to be a “human-caused fire” and is under investigation by the Wasatch County Sheriff’s Office, Wasatch County Fire confirmed.

A 90-person crew was reported to be at the scene, supported by helicopters and other aircraft, Wasatch County Fire noted.

Several single-engine tankers were deployed to drop water on the fire.

Mandatory evacuations, issued Thursday night for Little Sweden Road from 1200 East to Daniels Road, were lifted later in the evening “with the expectation that the homeowners must be ready to leave at a moment’s notice if fire conditions change,” Wasatch County Fire warned in its Facebook post.

Voluntary evacuations are in effect in the same area as well as from 1200 East to Highway 40 on Little Sweden Road, with a remaining threat to the homes further east reported.

“Downdrafts from potential thunderstorms, along with steep roads and limited access are some of the concerns for today [Friday],” Wasatch County Fire noted on Facebook.

Access roads to the fire are limited and residents are warned to be cautious when driving in the area and to not stop on the roads, Wasatch County Fire added.

Dubbed the “Big Hollow Fire” by local fire departments, the blaze sparked around 4:30 p.m. local time Thursday about a quarter-mile south of Daniel. Winds quickly pushed the fire north towards Daniel, Wasatch County Fire confirmed.

The area manager of the Utah Division of Forestry, Fire and State Lands, Mike Eriksson, told Utah’s KSL-TV Thursday: “It’s on a hill slope here. Oak brush, sagebrush, grasses. We’ve had dry weather here the past few weeks and it just went off here.”

Several people shared images, videos and updates of the fire on Twitter, including @JWojcikKSL, who noted: “This was only around 80 acres yesterday evening before winds picked-up and forced 50 homes to evacuate.”

“Scary fire in Heber tonight @KSL5TV #BigHollowFire,” wrote @bworgill.

“The fire is spreading like crazy! #BigHollowFire,” wrote @Brookewatters9.

“Looking better but all the smoke is much further east. #BigHollowFire How big is 500 acres? About 2 sq km or .8 sq mile,” wrote @robwcook.