Ritual murders have undoubtedly occurred in the past in the form of human sacrifice, and are still occurring today, for example in muti killings.
Serial killers are also known to perform ritualistic murders.
However, many false accusations of ritual murder have been made, often against ethnic minority groups. One famous example is the blood libel against the Jews, where Jews were said to kidnap Christian children and whip them and crown them with crowns before drawing off their blood for mixing into the unleavened bread eaten at Passover.
One lasting effect of the ritual murder charges in contemporary Jewish ritual occurs during the Passover seder, or evening meal, when a large goblet of wine is placed in the center of the table and the door is opened so that any onlookers can enter to see that no blood is added. Over the years, this cup became known as "Elijah's cup."