A man has been arrested and charged with the alleged murder of a camper in Montana, America, after the incident was initially reported as a bear attack.

Dustin Kjersem, 35, was found dead at a campsite north-east of Big Sky, Montana, on October 12 by his girlfriend and a friend, who at first believed he had been attacked by a bear.

When no bear was found in the area, the case turned into a murder investigation.

The Gallatin County Sheriff's Office has now confirmed Daren Abbey, 41, has been arrested and charged in connection with the death of Mr Kjersem.

Mr Kjersem had set up camp in the Moose Creek area and was due to pick up his girlfriend later so she could join him.

Mr Abbey, 41, had planned to camp in the same area but when he arrived he found Mr Kjersem already there.

Mr Kjersem welcomed him to the site and offered him a beer, Sheriff Dan Springer said.

"At some point this individual struck Dustin Kjersem with a piece of solid wood, stabbed him in the neck with a screwdriver and ultimately hit him with the axe," Sheriff Springer told a press conference.

"The motives of this attack are still unknown."

Sheriff Springer described it as a "heinous crime" and alleged Mr Allen had removed items from the campsite he believed could be used as evidence against him.

"By all accounts, this homicide appears to be a chance encounter," he said.

"There does not appear to be any connection between our victim and our suspect."

Sheriff Springer said detectives collected DNA from a beer can left at the campsite and it was a match to Mr Abbey.

He was tracked down this week and arrested in Butte, Montana, Sheriff Springer said.

Mr Abbey is being held on $2.2 million bail, according to sheriff's department records.