* MP says politicians use witchdoctors

* Warns albino killings will increase ahead of elections

* High Court says two trials have been stopped

MISUNGWI, Tanzania, Dec 1 (Reuters) - Rights campaigners say Tanzania must lift a shroud of secrecy surrounding wealthy buyers who commission albino killings for witchcraft, after one lawmaker admitted many politicians use witchdoctors themselves.

More than 100 suspects have been arrested in connection with the killing of 54 albinos, who lack pigment in their skin, eyes and hair. Body parts sell on the black market for up to $75,000 for a full set of limbs, genitals, ears, lips and blood.

But while seven men have been sentenced to death by hanging for involvement in two murders, no one who ordered the grisly trophies has so far been prosecuted for their role in what many Tanzanians say is a highly organised illicit trade.

"I find it conspicuous and puzzling that the people at the top end have not been named -- the people who actually have $3,000 to buy an arm," said Peter Ash, a Canadian albino and founder of lobby group Under The Same Sun. It plans to spend $1 million supporting albinos in the country this year and next.

"This is akin to the drug cartels where the people at the top are not named," Ash told Reuters.

The government banned traditional healers' licences in January in an effort to root out witchcraft after public attention was drawn to the killings. But politicians and campaigners say witchdoctors openly defy the ban and that the real source of demand has yet to be uncovered in court.

DEMAND UP AT ELECTION TIME

"I can assure you witchdoctors are still practising," said one member of parliament who did not want to be named because of the sensitivity of the subject.

"We at the political level also believe in witchcraft, so stopping it has got some political impediments to it."

The albino concoctions are meant to bring luck and are prized by miners, fishermen, business people and others seeking power and influence.

"At election time the demand for albinos is too high," the same politician said. Tanzania will hold national parliamentary and presidential elections towards the end of 2010.

The killings, in which machetes have been used to hack off limbs and mothers' breasts, beheading some victims while still alive, have tarnished Tanzania's reputation as a haven of peace -- the translation of its commercial capital Dar es Salaam.

One local BBC reporter who brought the albinos' plight to world attention left the tourism-dependent country following a series of death threats.

Of 54 trials, two court cases have concluded. High Court Registrar John Utamwa confirmed two cases had been stopped, including one last week, but said he did not yet know why.

"No one is above the law," Justice Ministry spokesman Omega Ngole said. "If you are involved, you should be taken to court." ((For a related story, please click on [ID:nGEE5B00EJ])) (Editing by Daniel Wallis and Jon Boyle) ((Email: nairobi.newsroom@reuters.com; tel: +254 20 222 4717)) (For more Reuters Africa coverage and to have your say on the top issues, visit:

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