BILLINGS, Mont. – Wielding his chain saw as a weapon, a Colorado man says he fought off a starving mountain lion that attacked him while he was camping with his wife and two toddlers in northwestern Wyoming.

Dustin Britton, a 32-year-old mechanic and ex-Marine from Windsor, Colo., said he was alone cutting firewood about 100 feet from his campsite in the Shoshone National Forest when he saw the lion staring at him from some bushes.

Britton revved his 18-inch chain saw and tried to back away. But the 100-pound lion followed.

As the animal pounced, the 6-foot-tall, 170-pound Britton raised his saw and met it head-on – a collision he said felt like a grown man running right into him.

“It batted me three or four times with its front paws and as quick as I hit it with that saw it just turned away,” he said in a telephone interview with The Associated Press.

Britton later discovered he’d inflicted a six- to eight-inch gash on the lion’s shoulder. He said he was surprised the damage wasn’t worse.

“You would think if you hit an animal with a chain saw it would dig right in. I might as well have hit it with a hockey stick,” he said.

The wounded animal retreated, leaving Britton with a only small puncture wound on his forearm.

The attack occurred Sunday evening at a campsite 27 miles west of Cody. Wildlife agents shot and killed the lion Monday after it attacked a dog brought in to track the animal.

Authorities say the lion was in poor physical condition and appeared to be starving. The lion was 4 to 5 years old.

Mountain lions are considered reclusive by nature and officials said the circumstances of the attack were highly unusual. Wyoming officials have documented only eight cases of mountain lions acting aggressively toward humans over the last decade.

After Britton’s confrontation, he and his wife, Kirsta, decided to stay the night in their pop-up camper with their two children rather than risk packing up with the lion still on the loose.

The next morning he told a passing U.S. Forest Service employee about the incident and that’s when wildlife agents were called.

Tests for rabies and other diseases came up negative, but officials said they were continuing to analyze the animal for other potential diseases.

“It’s very, very rare” for lions to attack, said Wyoming Game and Fish spokesman Warren Mischke. “We’re still trying to investigate why this lion would behave this way.”