Maine state police arrested Austin McDevitt, 22, Friday morning in Belfast in connection with the shooting death of Shane Sauer, 26, of Morrill.
Monday afternoon, McDevitt appeared before a Waldo County judge.
According to an affidavit prepared by a state police detective, both McDevitt and Sauer were involved with the same woman.
The affidavit detailing the events of the early morning hours Friday stated McDevitt told police he was sleeping at a Swanville camp with his girlfriend when Sauer broke in and start punching him.
The detective said shortly after the physical altercation, McDevitt approached an unarmed Sauer, shot him in the stomach from about 25 feet away, then shot him a total of three times as he was falling.
The court document said McDevitt then proceeded to within five feet of Sauer, firing four more bullets at him.
Police said McDevitt fired a total of 16 shots at Sauer, according to the affidavit.
Evidence against McDevitt is expected to be presented to the Waldo County grand jury within the next couple of months.