By Phil Mercer
BBC News, Sydney
Women are the target of a wave of sorcery-related murders
Police in Papua New Guinea are investigating a series of sorcery-related killings in the past week.
Authorities in the remote Highlands province of Chimbu say three women have been killed in two separate attacks.
One victim was burnt alive, while the others were stoned to death in killings described by police as gruesome.
The women were suspected of practicing sorcery and causing the deaths of several people in the community, Papua New Guinea media reported.
Senior police in Papua New Guinea said the latest three murders, in Chimbu province, north-west of the capital Port Moresby, were gruesome.
Two victims were pummelled by villagers armed with rocks and stones, while a third was burnt alive.
Two other women were rescued by relatives after they were locked away inside their home, which was then set on fire.
In some areas there is a belief that sickness and death can be caused by people with demonic powers.
Officials have said that a comprehensive awareness campaign is needed to address deep-seated fears about sorcery.
Attacks on suspected witches often go unreported and investigators invariably find it hard to penetrate tightly-knit communities.
Papua New Guinea is one of the world's most culturally diverse nations. More than 800 languages are spoken but levels of literacy are low.