LA PAZ--Bolivia's Catholic church has called on the faithful to stop using human skulls at special Mass celebrations, a practice some link to occult powers.

The Bolivian Episcopal Conference on Friday asked the overwhelmingly Catholic nation to cast aside the "growing" trend of seeking protection from bad luck by making offerings of coca, cigars or drinks to human crania.

As much of the world celebrates Halloween and Mexico prepares for its Day of the Dead, Bolivian bishops had another festival on their minds, the Day of Skulls, which falls on November 8.

Known locally as Natitas, the festival, which is believed to be pre-Colombian, sees families adorn skulls, sometimes those of relatives, with flowers, hats, candles and other decoration.

La Paz's Archbishop Edmundo Abastoflor warned many of the skulls in fact belonged to "unknown people, obtained by grave robbing and later conserved, donated or even sold."

Abastaflor urged practitioners of the Andean ritual to "let them rest in peace."