A cemetery dating to c 2400 BC have been unearthed in Syria.  The discoveries show that the death of a princess was commemorated by decapitating donkeys and sacrificing babies.

The newly-discovered tombs contained signs of the ritual sacrifice: underground brick structures yielded the skeletons of infants and decapitated donkeys or perhaps onagers (their wild cousins), as well as puppy bones, Prof [Glenn] Schwartz said. "Given these discoveries, it's likely that the tomb complex is a royal cemetery," he said. "Nowhere else in the region have we seen this elaborate example of animal sacrifices as part of burial rituals."
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The animal remains were sometimes found adjacent to baby bones, perhaps indicating that infant sacrifice went along with equid sacrifice in rituals honouring the important people buried nearby, Prof Schwartz said. Sets of puppy bones were also found in several of the brick structures. The archaeologists found spouted jars in the installations and a large jar containing the skeletons of three infants.

The archaeological site is believed to be the location of the lost city of Tuba, west of the Euphrates.  Tuba was the capital of a kingdom centred on the trade route between Mesopotamia (modern Iraq) and the Mediterranean.