An American woman has reportedly been gang-raped by an armed mob in Papua New Guinea, barely a week after an Australian was killed and his friend was sexually assaulted by a group of men in the impoverished Pacific nation.

The US academic told AFP she was attacked on Friday while conducting research on birds and the impact of climate change in a remote forest on Karkar Island in the Madang province.

The 32-year-old victim told police she was walking along a bush track with her husband and a guide when nine men armed with rifles and knives attacked them, stripped them naked then tied them up.

With her hands bound, the men allegedly cut off her hair to the scalp and took turns raping her for about 20 minutes before fleeing the scene.

The three were able to break free and fled naked to the nearest village, several hours away, the woman told a photographer working for AFP in Port Moresby.

Police in the capital confirmed the attack but said no arrests had yet been made.

The woman said she wants to publicize her ordeal to raise awareness on rampant brutality against women in Papua New Guinea, including domestic violence, which has become endemic in the country.

“This story should not come out because I am white,” the woman said. “It should come out in hopes that it empowers Papua New Guinean woman to stand up and say no more violence against women in this country”.