Ekimmu
Ekimmu One of the most fearsome creatures of the ancient world, found among the Assyrians and Babylonians, a departed spirit, the soul of a dead person who was unable to find peace. The creature wandered over the earth, waiting to attack. Its characteristics were very similar to the utukku, although the ekimmu was more widely known and more dreaded. There were many ways in which a deceased could become an ekimmu, including violent or premature death, dying before love could be fulfilled, improper burial, drowning, dying in pregnancy, starvation, improper libations or food offerings, and the failure, for various reasons, to be buried at all.
Taken from : The Vampire Encyclopedia – written by Matthew Bunson. Copyright © 1993 by Matthew Bunson
NOTE:
Since the Sumerians, Akkadians, Babylonians, Assyrians and others all shared essentially the same pantheon and belief systms, these articles are all combined under the Mesopotamian mythology / deities / legendary creatures category.