Buenos Aires, Argentina - A human skull, femur, and other bones were found on the altar, and detectives were investigating whether human sacrifices were carried out at the church in Argentina.
Police arrested the 44-year-old priest after allegations that he forced female followers into prostitution to raise money for the Umbanda cult, a spiritualist religious group which has followers throughout South America.
They made the grisly discovery of human remains when they searched the church in Moreno, Buenos Aires, where they also found live chickens and goats apparently ready for sacrifice.
The priest allegedly picked on the most vulnerable of his female congregation and after seducing them, threatened them with divine retribution if they didn't carry out his orders.
A relative of one of the victims realised what was going on and went to the police.
When they raided the temple, officers also found a book detailing the money the women were earning from prostitution, as well as liberating several terrified female followers who are now valuable witnesses.
A police spokesman said: "They are terrified. They think even from inside a cell the priest can harm them." Most of the female victims, married women in their 20s and 30s, had turned to the priest because they were poor and desperate.
The Umbanda religion is a blend of spiritualism, African religions and Catholicism which sprung up in the early 20th century among the impoverished black inhabitants of Rio de Janeiro.
At its height thirty years ago, it boasted 30 million members in Brazil alone, but now numbers just a few hundred thousand around the globe, mainly in South America.