Kenneth Hickman, 21, faces a felony charge of aggravated assault in connection with the murder of Gilbert George "Jack" Berry. Officials say Hickman didn't act alone. Mechailah Trembruell, 21, will face criminal charges as well.
Now investiagtors are searching for two more suspects, Kevin Lino and Angela Marchese. The duo left town and Trembruell told investigators they were heading to South Dakota.
Berry's body was found in the Clark Fork River earlier this week.
Bail is set at $150,000 for Hickman and $50,000 for Trembruell.
The charging affidavit says Berry's girlfriend saw Hickman, Lino, Marchese and Trembruell acting aggressively toward people when they arrived at a transient camp.
Berry then got into an argument with Lino and Hickman, and that's when Hickman allegedly knocked Berry to the ground. Court documents say both Lino and Hickman continued to beat up Berry and then they used a knife to cut gang signs into his body.
Another witness says he was at the camp later that night and saw Berry laying under a bridge with a bloody and swollen face. The witness says he saw Hickman kick and stick a lit cigarette under Berry's nose.
Witnesses say the two female suspects were not involved in physically harming Berry.
There is a nationwide search for Lino and Marchese. They are thought to be driving in a 2014 Ford Focus with West Virginia license plates.
Detectives are asking for anyone with information about the homicide to contact the Missoula County Sheriff's Office.