A man has admitted to killing a Montana hiker who was initially believed to be the victim of a bear attack, authorities say.

A man has admitted to killing a Montana hiker who was initially believed to be the victim of a bear attack, authorities said Thursday.

Dustin Kjersema’s bloody body was found Oct. 12 in a tent about two and a half miles up Moose Creek Road, east of Big Sky, after a friend who went looking for him called 911 and told dispatch, that Kjersem appeared to have been attacked by a bear, CNN previously reported. Authorities said Thursday that it was Kjersem’s girlfriend, who was concerned that he didn’t show up to pick her up, who found him dead.

After calling 911, investigators from several agencies, including a bear expert from the Montana Department of Fish, Wildlife and Parks, examined the area but found no signs of bear activity.

An autopsy found the 35-year-old man suffered “multiple puncture wounds,” according to the sheriff’s office. Investigators initially said they didn’t know what kind of weapon was used, “but we do know it was something hard enough to cause significant damage to the skull as well as some areas of the body.”

The sheriff’s office later noted that several items were missing from the crime scene, including a camp axe, shotgun, revolver and refrigerator.

“He was brutally murdered in his camp,” Gallatin County Sheriff Dan Springer said.

After a nearly three-week search, the sheriff’s office said it has identified the suspect, who is in custody “on unrelated charges.”

During the investigation, authorities collected DNA from a beer can left in the victim’s tent. They eventually made a match and arrested Daren Christopher Abbey, 41, who confessed to killing Kjersem, Springer said.

CNN is trying to determine whether Abby has an attorney.

Abbey told investigators he was in the area looking for a campsite and targeted where Kjersem was staying when he found the victim there, Springer said. According to Springer, the victim welcomed him to his luxury campsite and even offered Abby a beer before the fatal encounter.

At some point, Abbey hit the victim with a piece of hard wood, stabbed him in the neck with a screwdriver and hit him with an axe, Springer said. Abbey then allegedly removed items from the camp that he believed may have evidence linking him to the crime and later returned to the scene to remove other items, Springer said.

The motive for the attack remains unknown, but authorities believe Abbey acted alone and that the two men did not know each other.

“Investigators will continue to piece together what they can to piece together a more complete picture of the events that evening,” Springer said. “This appears to be a terrible crime committed by a man who had no regard for the life of Dustin Kjersema.”

“Our thoughts and prayers continue for Dustin Kjersema’s family. We hope that in some small way our efforts can bring them some peace during this terrible time. Our entire community mourns with you,” Springer said.

This story has been updated with additional information.

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