The Tete settlement in the Papua New Guinea capital of Port Moresby has been declared a fighting zone.
The declaration by Central police commander Geoffery Vaki comes after the revenge killing of seven people last week.
Mr Vaki has condemned the Tari people from the Southern Highlands for taking the law into their own hands after a tribesman was allegedly killed by one of the Goilala at Tete.
Mr Vaki says he also wants any evidence pointing to the killers coming from Tete.
He says the killings are barbaric and he is appealing to settlement leaders to prevent further fighting and property destruction.
Three other people were injured and 46 people have been arrested after fighting broke out last week.
Meanwhile the Moresby South MP and Social Development minister, Lady Carol Kidu, has appealed to people not to bring their customs for revenge on innocent people in the city.