Around 6000 people, mainly women and children, have fled into the forests from three villages during a wave of fighting and property destruction over the past week, the Post-Courier newspaper reported.
Provincial police commander Teddy Agwi said 300 PNG Defence Force personnel were helping 400 police officers protect government and other workers in the area's main town of Tari.
He said police could not make arrests as the two warring factions were using high-powered firearms and the police were outnumbered.
"We went into the villages of Oiebi, Mulimbi and Pinagia but they were empty.
"The people have escaped into the forests with their children to hide from their enemies," Agwi said.
The Post-Courier said the fighting erupted following an argument between two cousins over a piece of land that led to one of them being shot and killed.
