In 1989 a University of Texas student (Mark Kilroy) was abducted from S. Padre Island while on spring break, and taken to a ranch in Mexico. He was tortured for days and then became a part of a santeria ritual. He was ultimately beheaded. It’s a gruesome “religious” practice, Santeria is.
I have long viewed Santeria as demonically influenced. They practice possession/channeling of spirits, as well as the blood sacrifices you mentioned (including human sacrifice in some cases). Some of the African terms translated as “priest”, would probably convey the intent better as “sorcerer”.
Santeria is pretty synonymous with “VooDoo”, but it doesn’t (yet) have as much negative connotation in the public mind.