Over the past year and a half, a disturbing and violent trend has been growing in Malawi, a country often known by its nickname: "The Warm Heart of Africa." At least 18 people with albinism, a congenital condition resulting in a lack of pigment in the skin, hair and eyes, have been murdered, and many others have been raped or harassed. Four of the murders happened in April alone, and five more albinos have been abducted and are still missing.

A new report from Amnesty International accuses Malawian police of failing to protect the albino population, and the Malawian government of failing to educate its citizens about albinism's natural causes.

Albinism is more common in sub-Saharan Africa than elsewhere in the world. Superstitions about the condition are rife, especially in Malawi and neighboring Tanzania and Mozambique. Some believe that having sex with an albino woman can cure HIV, which puts albino women at particular risk for rape. Others believe that the bones of albino people contain gold, or have medicinal or even magical properties. That demand, stemming from a ritual medicine revival in Malawi, is fueling the spate of murders by gangs that, allegedly, can make as much as $75,000 selling a "full set" of albino body parts, according to the International Federation of the Red Cross.

"Their bones are believed to be sold to practitioners of traditional medicine in Malawi and Mozambique for use in charms and magical potions in the belief that they bring wealth and good luck," Amnesty said. "The macabre trade is also fueled by a belief that bones of people with albinism contain gold."

Separately from Amnesty, the United Nations recorded at least 65 cases of violence against albinos, including but not limited to killings and dismemberment, since the end of 2014.

Ikponwosa Ero, an independent expert who works with the United Nations on issues around albinism, told Al Jazeera that she thinks albinos in parts of southern Africa face extinction. "I said that this will happen over time if nothing is done," she said. "The situation is a potent mix of poverty, witchcraft beliefs and market forces which push people to do things for profit."

In a vacuum of public knowledge about the causes of albinism, many albinos are shunned by their families, and parents are often baffled by giving birth to albino children. The abductions and killings, some of which have been particularly gruesome, have instilled a culture of fear in the albino population. While Amnesty says that the police have done little to combat the rise of so-called "albino hunters," the police say they are doing everything they can. Last year, Malawi's inspector general of police authorized his officers to shoot any suspected "albino hunter" on sight.

“Shoot every criminal who is violent when caught red-handed abducting people with albinism. We cannot just watch while our friends with albinism are being killed like animals every day," Lexen Kachema said in April 2015.

Ero, the U.N. expert, who is an albino herself, said that albinos can't even die in peace. "Even in death, they do not rest in peace, as their remains are robbed from graveyards," she said.

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