BOISE, Idaho — Two wildfires that prompted the evacuations of two tiny towns in southwest Idaho and northern Nevada combined on Saturday to form a 600-square-mile blaze called the Murphy Complex.

Firefighters, aided by air tankers and helicopters, were trying to protect some 60 homes, 20 commercial buildings and 35 outbuildings in the sparsely populated area around Murphy Hot Springs, Idaho, and Jarbidge, Nev., said Brock Astle of the Bureau of Land Management.

“With the erratic winds and that sort of stuff, they’re doing the best they can,” he said.

The lightning-caused fire, burning mostly grass and sagebrush, was about 15 percent contained, he said. Two firefighters were treated at a hospital and released after one bruised his abdomen and another sprained his ankle.

Meanwhile, firefighters in northern Idaho battled the lightning-started Chimney Complex of fires about 20 miles south of Lewiston. A mandatory evacuation order was issued late Friday for residents of about 150 homes in the area.

Flames jumped a stream and were burning about two miles from the homes in the Waha Lake and Redbird Road areas, information officer Jennifer Costich said. But crews on Saturday managed to build a line around that part of the fire, she said.

“We’re feeling a lot better about it,” she said. “It is extremely tough conditions.”

The fire was burning in steep, rugged terrain, and one firefighter broke a leg after falling from a bluff, she said.

She said 427 people were working on the fire, with five helicopters assigned to the blaze with help from airtankers.

In all, 14 large fires burning in Idaho on Saturday had consumed about 935 square miles, the National Interagency Fire Center reported.

“We’ve got all different kinds of fires going on in Idaho,” said spokesman Ken Frederick said. “Timber fires, brush fires, grass fires, and we’ve got fires all over the state, too.”