Papua New Guinea's Police confirmed on Monday that 64 bloodied bodies have been found in the country's highlands, as officers reported ongoing gun battles between rival tribes.

Assistant Commissioner of Police Samson Kua said the bodies had been found after what is believed to be an ambush in the early hours of Sunday.

The incident occurred near the town of Wabag, 600 kilometers (370 miles) northwest of the capital Port Moresby. It is thought to be linked to a conflict between Sikin, Ambulin, and Kaekin tribesmen.

Highland clans have fought each other in Papua New Guinea for centuries, but an influx of automatic weapons has made clashes more deadly and escalated the cycle of violence.

Kua said the gunmen had used a veritable armory, including SLR, AK-47, M4, AR15 and M16 rifles, as well as pump-action shotguns and homemade firearms.

It is believed that fighting is ongoing in a remote rural area nearby.

Papua New Guinea's highlands have been the scene of persistent tribal violence, with several mass killings in recent years.

The country's government has tried suppression, mediation, amnesties and a range of other strategies to control the violence, with little success.

The military had deployed about 100 troops to the area, but their impact has been limited and the security services remain outnumbered and outgunned.

The killings often take place in remote communities, with clansmen launching raids or ambushes in revenge for previous attacks.

Civilians, including pregnant women and children, have been targeted in the past. The murders are often extremely violent, with victims hacked with machetes, burned, mutilated or tortured.

Opponents of Prime Minister James Marape's government on Monday called for more police to be deployed and for the force's commissioner to resign.