Pure Blood

Pura Sangre is a 1982 Colombian drama thriller horror film directed by Luis Ospina starring Gilberto Forero, Carlos Mayolo, Florina Lemaitre, Humberto Arango and Luis Alberto García. The film is based on true events about the 'Monster of the Mangones'; apparently Adolfo Aristizabal, a sadist, psychopath who murdered 30 children between the ages of 8 and 13 and an unsolved case in the Colombian justice system. They were mostly street dwellers or young people who walked near the Mangones; an area of Cali where there were unbuilt spaces and buildings are isolated from each other, making it easy to capture anyone in the dark of night. To this was added the myth that the person presumed responsible for these deaths was a wealthy man who suffered from leukemia and the appearance of him was dying and cadaverous. So, to survive, the alleged man would have hired people to kill young people and survive on his blood, either with transfusions or by drinking it.

Synopsis from Wikipedia, CC BY-SA 4.0. Everything below written here.