The airport has launched an appeal for the safe return of the figure, which has been the focus of the nativity scene at Terminal One for five years.
An airport spokesman began the appeal: "Members of staff noticed the disappearance, and in the true spirit of Christmas we would like to appeal to whoever is responsible to return the baby Jesus as soon as possible.
"The prank has not gone unnoticed with our passengers either and our terminal managers have been dealing with difficult questions from many young passengers as to why the airport's nativity crib is incomplete."
Passengers have even taken to Twitter to discuss the missing baby Jesus, with one commenting: "I think someone has stolen Baby Jesus from @manairport."
Fortunately Terminal Two's Christmas decorations, which include a tree and dancing penguins, have remained in their rightful place.
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