To kill infant Krishna , Kamsa had deputed several demons. One of them took the form a Giant Crane and tried to kill Sri Krishna. The demon who took the form of Crane was called Baka (Bakasura) and he was the sister of Putana, who had earlier failed in her attempt to harm Krishna by feeding poisoned breast milk.
Baka took the form of a giant crane and carried Sri Krishna away in his beak. He then attempted to swallow Krishna . To escape from the throat of the bird, Sri Krishna produced intense heat. The bird felt as if it had swallowed burning coal. The bird threw infant Krishna out.
Then the bird attempted to kill Sri Krishna by biting. But Krishna caught hold of the beak and tore it apart. He thus killed demon Baka.