A tribe, their allies and mercenaries were on their way to attack a neighbouring tribe when they were ambushed Sunday in Enga province in the South Pacific nation's remote highlands, Royal Papua New Guinea Constabulary Acting Superintendent George Kakas told Australian Broadcasting Corp.

Police expected to find more dead bodies among the wounded who had escaped into the woods, he said. “These tribesmen have been killed all over the countryside, all over the bush,” Kakas told ABC.

Bodies were collected from the battlefield, roads and the riverside, then loaded onto police trucks and taken to the hospital. Kakas said authorities were still counting “those who were shot, injured and ran off into the bushes.”

“We presume the numbers will go up to 60 or 65,” he said.

Kakas said it could be the highest death toll from such violence in the highlands, where there are few roads and most of the inhabitants are subsistence farmers.

Police in the capital of Port Moresby did not immediately respond to the AP's request for information on the massacre.

Papua New Guinea is a diverse, developing nation of 10 million people with 800 languages in a strategically important part of the South Pacific.

Internal security has become an increasing challenge for its government as China, the United States and Australia seek closer security ties.

Australian Prime Minister Anthony Albanese said his government was ready to assist Papua New Guinea, which is Australia's nearest neighbour and the largest single recipient of Australian foreign aid.

“That is very disturbing the news that has come out of Papua New Guinea,” Albanese said.

“We remain available to provide whatever support we can in a practical way, of course, to help our friends in PNG,” Albanese added.

Albanese said Australia was already providing “considerable support” for Papua New Guinea and was helping train the country's police officers.

Tribal violence in the Enga region has intensified since elections in 2022 that maintained Prime Minister James Marape's administration. Elections and accompanying allegations of cheating and process anomalies have always triggered violence throughout the country.

Enga Gov. Peter Ipatas said there were warnings that tribal fighting was about to erupt.

“From a provincial perspective, we knew this fight was going to be on and we (alerted) the security forces last week to make sure they took appropriate action to ensure this didn't occur,” Ipatas told ABC.

Ipatas described the violence as a "very, very sad occasion for us in the province and it's a bad thing for the country.”