Thabo Nsako, a Cosas leader from Soshanguve, told traditional healers at a seminar held by the Gauteng legislature in Pretoria that they should never kill for muti.
"Your duty is to protect us, not to kill us. Ancestors can never [tell] you to kill people," he said.
He said Western countries viewed the practice as witchcraft and wanted nothing to do with it because of such practices as muti-killings.
"It is your fault."
Referring to the murder of 11-year-old Masego Kgomo in what police believed was a muti-murder, Nsako said: "Those who killed Masego are animals. They deserve to rot in jail and never come back."
The girl's badly decomposed and apparently mutilated body was found hidden in a dense clump of bushes near her Soshanguve home.
A sangoma was reportedly arrested for the murder.
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