Police in Rotorua are warning against vigilante action after reports people are plotting revenge for fights at several parties.
They say there have been numerous out-of-control parties in Rotorua in recent months.
Six people were admitted to hospital after a brawl two weeks ago. Two had skull fractures and a third needed about 30 stitches to his face.
Since then, two youths have been charged with assault and police have heard more attacks are planned.
Inspector Ed Van Den Broek says violence of any kind won't be tolerated and the police won't condone anyone taking the law into their own hands.
They want anyone with information about planned retaliation or disorder to contact them.