Sister Ines Nieves Sancho's body was found early Monday in the village of Nola, located in the remote southwest near the borders with Cameroon and the Republic of Congo.
Local authorities condemned the killing but suggested it may not be linked to the ongoing sectarian bloodshed between militia groups that first engulfed the country in 2013.
"Elsewhere it's the rebels who kill, but in Nola people kill to get rich," said Jean Marc Ndoukou, an official in the village located about 135 kilometers (83 miles) from Berberati, the country's third largest city and traditionally a center of diamond production.
Authorities also said ritual crimes are not uncommon in and around Nola and perpetrators are rarely punished.
Ndoukou vowed that the unknown attackers would be punished, and the country's parliament called for an investigation.
On Wednesday, Pope Francis led thousands of people in prayer for Nieves Sancho, saying she was "barbarously killed" in the place where she taught. The Vatican said she had worked with the poor for decades.
Sectarian violence exploded in Central African Republic in late 2013 after mostly Christian and animist militia fighters retaliated against Muslim civilians following a brutal rule by a mostly Muslim rebel government. Violence engulfed the capital and the southwest where an untold number of Muslims were slaughtered as they attempted to flee to Cameroon.
A presidential election was held during a period of relative peace in 2016 though instability later returned to many parts of the country. Despite several peace agreements, including one earlier this year, the country remains plagued by conflict.
Associated Press writers Angela Charlton in Paris, Nicole Winfield in Rome and Krista Larson in Dakar, Senegal contributed.
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