Three investigations are under way into "potential excessive use of force" by guards responding to the stabbing of an officer at the maximum security Auckland Prison at Paremoremo.
Two officers were suspended after the incident on May 20, which is believed to be part of a series of tit-for-tat events involving Killer Beez gang founder Josh Masters.
According to a well-placed source, the sequence began in late April when Masters and another prisoner allegedly punched a female prison guard in the face.
Prison officers responded by "throwing punches of their own", said the source. One allegedly punched Masters, who is serving a 10-year sentence for drug-related offending, and pushed him to the ground.
Masters, a former kickboxing champion and aspiring rapper was moved to the isolation unit where it's believed he remains.