The way a woman walks can be a death sentence in Papua New Guinea, where the ancient world of witchcraft has collided brutally with the modern plague of AIDS.
Women accused of being witches have been tortured and murdered by mobs holding them responsible for the apparently inexplicable deaths of young people stricken by the epidemic, officials and researchers say.
How the women are singled out for such a fate can be as cruel as their treatment, said Joe Kanekane of PNG's Law and Justice Sector Secretariat.
"People believe a witch would behave in a certain way, would walk in a certain way. That's all the basis that they have and there's realistically no tangible substance to it," he told AFP.
"They don't actually see the woman transform herself into a python or whatever it is (witches are reputedly capable of). Witchcraft is embedded in people's perceptions, embedded in their way of life."
Less than a lifetime ago some tribes in this rugged South Pacific island nation off the northeastern tip of Australia had never had contact with the outside world.
It remains one of the most intriguing lands on earth, with more than 800 languages spoken by a population of just six million spread thinly through rainforests, tropical islands and mist-shrouded mountains.
But a recent United Nations report said PNG was facing an AIDS catastrophe, accounting for 90 percent of HIV infections in the Oceania region.
HIV diagnoses had risen by around 30 percent a year since 1997, leaving an estimated 60,000 people living with the disease in 2005.
High levels of sexual violence against women and poor access to sex education had helped the virus ravage PNG's population, the report said.
For some, ancient beliefs have provided an instant and brutal answer to the bewildering new disease.
-- Cultural confusion sees disease blames on supernatural forces --
"Sorcery, witchcraft and other supernatural forces are widely blamed for causing HIV/AIDS," the Centre for Independent Studies in Australia said in a recent analysis.
"Accusations of sorcery have resulted in torture and murder. The ?mysterious? deaths of relatively young people, thought to be deaths from HIV/AIDS, are being blamed on women practicing witchcraft.
"There are reports of women being tortured for days in efforts to extract confessions," wrote research fellow Miranda Tobias.
"Women have been beaten, stabbed, cut with knives, sexually assaulted and burnt with hot irons. One woman had her uterus ripped out with a steel hook.
"It is estimated that there have been 500 such attacks in the past year," the independent think tank said.
In one recent example in the port city of Lae, two alleged witches blamed for a young man's death were tortured and then set on fire by an "animalistic and inhuman" mob, said regional police chief Giossi Labi.
"This is a city and one would think people would be more civilised," said Labi.
PNG's only female member of parliament, Carol Kidu, has spoken out strongly against witch killing.
"Sorcery permeates many societies in Papua New Guinea, and these young deaths from HIV/AIDS are unexplained and so they attach it to sorcery, they make it witchcraft," she told AFP.
Ancient belief in the supernatural sits comfortably with Christianity for many Papua New Guineans, whose forefathers were exposed to US and European missionaries as soon as first contact was made with the isolated tribes.
"It (witchcraft) does exist," said military doctor Roselyne Wia. "I'm a Christian and I do say there's a God and there's the devil -- it does exist."
The only way to end the killing of "witches" blamed for AIDS deaths, however, would be to "educate the village leaders and get the message down to the grassroots," said Wia.
The 32-year-old doctor said that as a Christian who does not believe in sex outside marriage she has had to overcome her own initial reluctance to promote the use of condoms by soldiers to combat the spread of HIV.
"Then I realised, hey, I'm not protecting the women and the children. Every soldier has a condom in his pocket now -- I call it body armour," she laughed.
Wia is frank about the strains caused by the rapid transition from the tribal warrior's life lived by her grandfather to her own place in the modern world as a qualified doctor and captain in the army.
"It's just leaving us totally confused. The developments are so fast and we're not given time to adapt," she said.