"The government must conduct a full investigation into the matter and arrest the perpetrators," said UN country chief, Alvaro Rodriguez, after visiting the worst affected regions in northern Tanzania on Friday. He urged Tanzania to give the investigation the "highest priority" and expressed "outrage" at a series of attacks on albinos, whose body parts are sold for witchcraft.

"We'll do what we can in cooperation with the government to ensure that the girl is brought back," Rodriguez said.

Armed kidnappers seized four-year-old Pendo Emmanuelle Nundi on December 27 from her home in the northern Mwanza region. The police have since arrested 15 people, including the girl's father and two uncles. Police authorities have also given villagers five days to find the missing girl.

They abduct them, kill them and sell their body parts

Top local government official Magesa Mulongo visited the village appealing for more information on the kidnapped child. "The whole world now considers the villagers as having no heart," Mulongo said.

In August last year a UN rights expert warned that attacks against albinos were on the rise because Tanzania's October 2015 presidential election was on the horizon, encouraging political campaigners to turn to influential sorcerers for support.

The Tanzanian government's system of rounding up children with albinism in state-run education centers isn't adequately protecting them from widespread superstitious belief that human albino body parts will bring wealth and success, or cure disease. That's why kidnappers usually armed with machetes abduct albino children, kill them and sell their body parts for around $600 (with an entire corpse fetching $75,000).

1,400 people with albinism

People with the genetic condition, characterized by a lack of pigment in the skin, are often referred to as ghosts in Tanzania, or as "zero zero", which means someone who is less than human in the Swahili language. Witch doctors often lead brutal attacks to use albino body parts in potions they claim bring riches.

One out of every 1,400 citizens in Tanzania has albinism. By comparison, the global average is about one in 20,000 people, according to Canada-based albinism advocacy group Under the Same Sun.

jil/gb (AFP/AP)