Three traditional healers in northern Tanzania have been arrested for defying a government ban issued last month.
It was meant to stop killings of people with albinism for ritual medicine.
Their arrest follows charges against a pastor, who was allegedly found in south-western Tanzania in possession of the body parts of an albino.
The BBC's Vicky Ntetema in Dar es Salaam says this case is blow to people with albinism, some of whom have been seeking refugee in churches.
The pastor - Cosmas Mwasenga - was arrested in the Mbeya region and faces the death penalty if found guilty.
The three traditional healers had been travelling around the northern district of Serengeti in a car using a public address system to let their clients know that they were still open for business.
Their arrests come days after the murder of a 14-year-old albino girl in the northern Mwanza region, bringing the national death toll to 45 since mid-2007.
The killers reportedly sell albino body parts - including limbs, hair, skin and genitals - to witchdoctors to make potions that purport to make people wealthy.
Our reporter says more than 200 people - including witchdoctors, their clients, hired killers and some of the victims' relatives - have been arrested in connection with the killings in the last year.
No-one has so far been convicted, she says.
There are thought to be more than 200,000 albinos in the country, which has a total population of 40 million.