A Cleveland Police spokeswoman said the 22-year-old man arrested in connection with the incident has been released on bail.
The injured man remains in an induced coma in hospital, police confirmed.
Officers say they have been searching for all evidence from the scene. It is unclear whether they have found the missing penis.
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Patchy cloud and a few spells of sunshine expected on Sunday for the NE. An odd patch of rain is possible anywhere
A group of protesters angry at threats of closure to children's centres in Newcastle have marched on a council-run surgery.
Breezy 24 hours, but not a bad Sunday in prospect