The suspect was identified as 24-year-old Max Meako from Gulf Province.
Meako was apprehended by Kerema police a week ago and handed over to the Homicide unit.
He was formally arrested on Thursday with 1 count of wilful murder.
Meako had allegedly stabbed and killed the Hagen man in late October in Kerema town because he (deceased) had refused to hand over cash and belongings.
The relatives of the deceased then retaliated and caused chaos along the highway.
