Trekkers attacked by PNG bandits tell of horror

A group of Australian and New Zealand trekkers brutally attacked by bandits in Papua New Guinea told Thursday of their harrowing ordeal and horror as two porters were butchered.

The eight tourists were in their tents on the remote jungle-clad Black Cat Track in the lawless Pacific nation's northern Morobe province when a mob of six armed men struck at dusk on Tuesday.

Two porters were hacked to death with machetes and four of the Australians were injured, including one who was speared through the leg.

"It started to rain and some of us were inside the tents when there was a whole lot of noise, shouting. I thought the boys had found a bush kangaroo, an animal or something like that," one of the survivors, Nick Bennett, told Channel Nine after arriving in the capital Port Moresby.

"Next thing, I thought 'what's going on', I put my head outside tent and smack -- I thought I'd been shot actually," he said of being hit with a rifle butt.

"Blood just erupted out of my head and I looked up and I saw this guy with a mask on standing over me, and then the whole thing unfolded.

"They were laying into the porter boys. I realised they were butchering the porters. It was just appalling and we're very fortunate."

Another survivor, Peter Stevens, told Australian Associated Press he and the rest of the group were forced to lie on the ground as the men ransacked their backpacks, stealing passports and other items.

"They then laid into us with bush knives, hitting us with the flats of the knives," Stevens said.

"You can't tell whether they're going to hit you with the flat side. Some people were cut."

Stevens said two of the attackers were clearly on drugs and "they did the most damage".

The group managed to hike some four hours back to safety, reportedly carrying the porters' bodies.

Papua Prime Minister Peter O'Neill vowed the tribesmen responsible will face the death penalty if caught and convicted.

"I make no apology whatsoever for the death penalty being the punishment available to be applied for such crimes," he said in a statement.

While the attack was believed to be a robbery, some reports suggested it could also stem from growing resentment that the booming trekking industry is not giving back to local communities.

Crime in Papua New Guinea is rampant, including in Port Moresby where in June four Chinese nationals were hacked to death, with one reportedly beheaded and the others dismembered.

Brutality against women is particularly endemic, with high rates of domestic violence. In April, a US academic was gang-raped while she was trekking along a jungle trail with her husband and a guide.

The Black Cat Track runs between Wau and Salamaua in northern PNG through leech- and snake-infested jungle with precarious drops and potentially dangerous river crossings.

It was the scene of bitter fighting in 1943, pitting Australian and US troops against Japanese forces.