They are burnt, stoned, slashed, poisoned or hanged. They range from the young to the elderly and more often than not they are women. Often they are killed by mobs of men but sometimes they face kangaroo courts. They are the “sorcerers” of Papua New Guinea — victims of a literal witch-hunt in one the world's poorest and most isolated countries.

There have been more than 50 murders in recent months of people accused of practising black magic, according to human rights organisations. Authorities appear helpless to intervene although the Government has ordered a parliamentary commission to spend a year investigating ways to prevent witch-hunts, which arise from a tragic combination of tribalism, underdevelopment and superstition.

“When dozens of people have been killed, it's clear that the Government is not doing enough to protect its own citizens and maintain the rule of law,” said Apolosi Bose, of Amnesty International.

The persecution of the practitioners of black magic has a long history here in the eastern half of the vast tropical island of New Guinea, north of Australia. Media reports suggest, however, that in the past year it has become an epidemic, especially in the Highlands region, parts of which had their first contact with Westerners only as recently as 70 years ago.

Last Sunday a father and son were burnt alive close to Mount Hagen, the capital of Western Highlands province, after neighbours accused the older man of causing the death of a local leader by sorcery. In January a young woman was burnt alive on a pyre of rubber tyres after being accused of witchcraft and of passing on HIV/Aids to men with whom she had extramarital affairs. One married couple escaped a lynch mob when the pregnant wife began to give birth as she was being hanged from a tree.

Last Friday a court in the town of Lae sentenced Wilson Okore, 29, to 50 years in jail after he hacked to death a forest warden for allegedly using spells to give a woman colleague headaches.

Accusations of witchcraft sometimes seem to be the pretext for the settling of local scores, and tend to be made by families who have lost a loved one to a disease without an obvious cause. Often this is cancer or, increasingly, Aids-related illnesses, which are spread by prostitution, scant use of condoms and high rates of rape and sexual violence against women. Victims of witch-hunts are often women who have married into a community from another tribe and who lack kinsmen of their own to defend or avenge them.

The objective existence of black magic is enshrined in Papua New Guinea's 1976 Sorcery Act, which permits white magic but punishes the black variety with up to two years in jail. The country's police force is poorly trained, poorly resourced and riddled with corruption, so witch-hunters have a good chance of escaping punishment.

“People often don't trust the police or the judiciary and instead blame events on supernatural causes and punish suspected sorcerers,” said Mr Bose.

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