The veracity behind police operation in Papua New Guinea — which resulted in five civilian deaths — has prompted calls for an independent investigation over conflicting accounts between police and community members.

Concerns are held over a growing public rift in the Enga province's Tsak Valley over community trust in the Royal Papua New Guinea Constabulary carrying out their day-to-day duties.

An incident which has caused concern for residents occurred in the early hours of January 2, amid an operation under an anti-terror policing framework.

Despite being described as a success, the operation has drawn heavy criticism from civic leaders and traditional Papuan clansmen.

Acting Police Commissioner Samson Kua said in a statement security forces commenced operations shortly after 3am "executing coordinated raids on two locations" in the Tsak Valley.

The objective, he said, was to locate and apprehend suspects believed to be in possession of factory-made firearms linked to tribal fighting and forms of criminal activity.

Various sources have indicated Winis Kaki, who was previously described as a "warlord" in the area, was one of the primary suspects, and a prominent member of the Yambaran Warenge tribe, one of four large tribes in the area, was armed during the raid when police shot and killed him and his primary school teacher wife, Margaret.

The other victims among the five deaths were identified as Nancy Kipongi, 60, a once prominent ward councillor in the Tsak Valley, Glendale Taso, 30, and Isaac Ipu, 27, who was reportedly shot in his own food garden.

In the statement, police said officers attempting entry at the first location, which was identified as Winis Kaki's residence, were met with gunfire from inside the dwelling, wounding one shocked office.

Police returned fire, killing an "armed suspect", before recovering an M16 rifle and a loaded magazine.

Another armed individual was also shot dead during the operation, police say.

In its statement police also confirmed the arrest of Joseph Tati, a Christian pastor and community leader.

Officers recovered a second M16 rifle, a modified .38-calibre revolver and ammunition while three additional suspects, which were believed to be unarmed, were also arrested.

"This engagement, which lasted over an hour, demonstrates our resolve to disarm these groups despite the high risks involved," Act Comm Kua said.

Police intelligence indicated the seized rifles were being used as "hired guns" in tribal conflicts.

Community accounts in the Tsak Valley differ from that of police, according to several media reports.

Observers of the incident allege there was excessive lethal force in use during the operation, specifically regarding the deaths of both women, according to a Radio New Zealand reporter on the ground.

Videos recorded after the raid show multiple spent bullet casings near a hut where the victims were shot.

A Tsak Valley clansman, who did not want to be identified, said his cousin was among those killed while claiming at least one of the young men who died was not armed at the time.

He acknowledged firearms are widespread - said to be kept for what most residents describe as protection.

"Many arm themselves for protection against their tribal enemies," the clansman said.

"It is also no secret that prominent members of the community are often expected to contribute resources, including weapons, to support their tribesmen."

Police have not responded to the claims.

The PNG government has moved to strengthen its legal framework and policing response in recent years to escalating violence involving illegal firearms and large-scale tribal fighting.

Amendments to existing firearms legislation have significantly lifted penalties for the unlawful possession, use and trafficking of guns.

Some offences carrying life imprisonment under the national government's recent legislation.

The new laws address what the government has described as domestic terrorism, including the establishment of anti-terror policing capability, to expand police powers to act against organised armed groups that pose threats to public safety.

Prime Minister James Marape has publicly backed the Tsak Valley operation, warning against the continued use and possession of illegal firearms.

"Police were acting on intelligence relating to known hired gunmen operating within the province (Enga)," Mr Marape said.

Mr Marape also reaffirmed the government's zero-tolerance policy on illegal firearms, warning communities against harbouring gunmen.

He added where innocent people are affected during operations, the state — and not individual police officers — would take responsibility, subject to a "proper" investigation.

Family members of those killed are said to be preparing petitions to the national government to call for an independent investigation into the conduct of the raid in addition to greater accountability for the deaths of innocent bystanders.