Police in the Simiyu region said the 40-year-old victim was murdered overnight earlier this month and the attackers had hacked off her left leg, the index and middle fingers of her left hand and part of her left thumb.
Photographs of the murder scene outside her home were too graphic to publish.
People with albinism are often subjected to violent attacks in the country, where they are known as the “zeru zeru” or ghosts.
The condition is heavily stigmatised and families who see it as a curse have known to kick relatives out of their homes.
But sufferers are also a target for traditional healers, who harvest body parts to make potions for wealth, success and even election victories.
Albinism campaign group Under the Same Sun said the latest victim was the 73rd person with albinism to be killed in Tanzania since the year 2000 and 67 others have suffered violent attacks during the same period.
The group’s founder and chief executive, Peter Ash, said: “The life of yet another person with albinism has been snuffed out.
“[The woman] was mutilated and violated in the most barbaric way, because of the fatal discrimination people with albinism face in Tanzania.
“Her screams must rouse the international community to demand the Tanzanian authorities locate and punish her killers to the fullest extent of the law.
“Anything less is a flagrant miscarriage of justice, perpetuated on the most vulnerable.”
The two arrested witchdoctors, a 45-year-old man and 52-year-old woman, were reportedly known in the victim’s village and police are also hunting for her boyfriend.
Police said the woman had two children and had sent her eight-year-old daughter to a witch doctor on the day of her murder for herbal medicine to treat her backache.
The healer reportedly told the girl not to return home to her sick mother because it would stop the “medicine” working and instructed her to stay with her aunt.
That night, the woman was murdered and her grossly mutilated body was discovered outside of her home by her niece the next morning.
Under the Same Sun is campaigning for better protection for people with albinism in Africa and wants to see witch doctors banned as they claim current regulation is not working.
The group is concerned that attacks will increase in the run-up to elections in October, when the demand for potions made from albino body parts is expected to increase.
Killings have been less frequent in recent years and the Tanzanian government, which has one albino MP, has been trying to address the problem.
Source: The Independent