This is an archived article that was published on sltrib.com in 2016, and information in the article may be outdated. It is provided only for personal research purposes and may not be reprinted.

One stubborn lightning-caused fire down, three to go for southern Utah firefighters as of Monday, but near-record heat will plague crews' efforts to hem in the remaining blazes in the days ahead.

As if the searing sun and near triple-digit temperatures weren't enough of a challenge, the appearance of illegal drones flying over the flames — despite frequent warnings of possible misdemeanor or felony prosecution — has added to the danger for air tanker and helicopter crews.

Late Sunday evening, at least two incidents involving the small, remotely operated aircraft were reported, resulting in fire retardant and water dumping runs being halted over to safety concerns.

Specifically, the drones violated the 5-mile flight restriction zone over the 318-acre Saddle Fire, which continued to burn Monday in tinder-dry brush, grass, pinyon and juniper about 2 miles southwest of the town of Pine Valley. The Saddle Fire still was deemed out of control.

Due to the fire's rocky, steep and hard-to-access terrain in the Dixie National Forest, uninterrupted air support has been critical. U.S. Forest Service spokeswoman Wende Wilding estimated that as of Sunday night, nearly 17,000 gallons of fire retardant had been dumped on the Saddle blaze alone.

A drone flying around the area led to crews pulling back air support for two and a half hours Monday evening. Air operations resumed about 5:20 p.m., but they were halted again Monday night after a drone buzzed a firefighting helicopter in "an attack on the safety and wellbeing of our flight crews and our aircraft," said Chris Henrie, the Saddle Fire incident commander, in a news release Monday evening.

The Washington County Sheriff's Office asks that anyone with information on the drone flying around the fire call the agency at 435-634-5734.

The nearby Pine Canyon Fire was 76 percent contained at 105 acres as of Monday morning. It was smoldering about 2 miles south of the Aspen Fire, which was 50 percent contained on Sunday.

"Crews continue to make good progress securing the fire edge and mopping up hot spots with helicopter support," Wilding said.

The Sand Mountain Fire was 70 percent contained, having burned 111 acres, about 5 miles southwest of the Little Sahara Recreation Area.

Twitter: @remims