Two people are in hospital with fractured skulls after fights which erupted when a series of parties were held in the same area.
Police were called to a large-scale disorder at the intersection of King St and Pretoria St about 11.20pm on Friday and established there was a series of parties in the same Pretoria St flat complex.
At least one of the parties was said to have been advertised on social networking website Facebook as an open invite. The parties had attracted between 100-150 people in their late teens and early 20s. Police said at least six people were injured as a result of the fights which broke out. All six were taken to hospital and two remain in Waikato Hospital with fractured skulls.
Of the other four, one suffered a serious cut to his face, which required numerous stitches, and another suffered a nasty head injury.
Police want to hear from anyone who was in the area and who saw the fights break out. They also want information about people who may have been armed with various objects, which were being used as weapons and also anyone else who may have been injured.
The call comes as police warn about the increase in out-of-control house parties, which are ``fuelled'' by excessive drinking.
Bay of Plenty police prevention manager Inspector Scott Fraser said officers regularly came across youths wandering the streets at weekends looking for parties.
Mr Fraser said police were not out to stop people from having a social drink or having a good time.
"The issue is excessive drinking that is leading to poor decisions, like fighting and driving drunk. Youths in particular are leaving themselves vulnerable to becoming victims of crime because they are allowing alcohol to inhibit their perception of a safe environment,'' he said.
"More often than not the situation has escalated to disorder before we are called and valuable resources that could be better utilised protecting our communities and helping victims of crime are being tied up.''
Mr Fraser said prevention was the key to breaking the cycle.
"Party hosts need to be taking greater responsibility and we all need to get better at looking out for family, friends and neighbours, as well as ourselves.''
Mr Fraser said throughout the summer, there would be operations focused on alcohol harm which would be a combination of education and enforcement.
Mr Fraser said tips to holding a safe party included letting police know what was planned, avoiding advertising the party on social media and only inviting those who wouldn't cause trouble.
"If you know of a party being planned in your community let us know in confidence.
"Knowing what is going on in our communities helps police to make sure they have the right people in the right places at the right times and helps police staff to provide effective crime preven tion and safety advice,'' he said.
"If drinking is becoming excessive or starting to get out of hand call the police before it escalates out-of-control.''
Anyone with information about the disorder on Friday night should contact Rotorua police on (07) 349 9400.