Papua New Guinea's prime minister Peter O'Neill says he has directed a police investigation into the killing of a student at the University of Technology in June.
A first-year student Graham Romanong was killed in his room at a dormitory at Unitech in Lae and various buildings on campus were burned.
The killing came amid differences among students over a boycott of classes, calling for the Prime Minister to stand down to face fraud allegations.
In Southern Highlands province last week, Mr O'Neill told a large crowd at Umbimi village outside Mendi, understood to include the deceased's relatives, that the perpetrators of the killing would face justice.
He said he'd issued a prime ministerial directive for Police Commissioner Gari Baki's personal commitment to fully investigate, arrest and prosecute all persons involved in planning, financing and carrying out the killing.
Within a few days of the killing, Lae police arrested three people for questioning over the killing.
The prime minister, who is also from Southern Highlands, thanked the victim's relatives, tribesmen and the Kambiri people for not taking the law into their hands by seeking revenge after the killing.
"You acted in a civilized and matured manner and demonstrated leadership in containing what could have exploded into major ethnic conflict resulting (in) loss of lives and destruction to properties," he said.
"We can't be like them (killers), because it is a primitive act, barbaric and animalistic behaviour," the Prime Minister stressed.