Detective Senior Sergeant Mark Dalzell said police had spoken to dozens of people as part of their inquiries and thanked them for their assistance.
"Police are not seeking anyone else in relation to Krillan's death and we hope today's update provides some reassurance for the local community and to his family, who we are continuing to support during this difficult time."
Police could not comment further while the matter was before the courts, Dalzell said.
About 30 people were understood to be at the party when Koni Brown died.
Meanwhile, police have arrested 19-year-old David Mane after a major manhunt focused on Moerewa.
It is alleged Mane fired a shotgun at another man at close range on Wynyard St in Moerewa last Saturday. The victim survived but required surgery.
Mane then went on the run, sparking a manhunt that lasted almost a week and at times involved the Armed Offenders Squad sealing off parts of Moerewa.
Moerewa School went into lockdown briefly on Wednesday while police searched nearby addresses, then on Thursday opted to close for the rest of the week or until Mane was found to avoid further trauma for the children.
Many Moerewa residents used social media to call on Mane to give himself up and prevent further distress in the town.
Inspector Riki Whiu, Police area commander for the Far North, said a 19-year-old was located in Kawakawa early yesterday morning and arrested with the assistance of the Armed Offenders Squad.
The arrest was the direct result of information received from the public.
"We want to extend our thanks to our Moerewa and Kawakawa communities for assisting police, providing us with information and tolerating our increased armed presence,'' Whiu said.
"I also want to acknowledge the efforts of our staff who have worked tirelessly over the past week to hold this offender to account. We hope this morning's arrest will provide some reassurance to these communities who I know do not stand for behaviour which continues to put them at risk.''
Mane appeared in the Kaikohe District Court yesterday afternoon on charges relating to multiple alleged incidents over the past month.
His charges include wounding with intent to cause grievous bodily harm, threatening to kill, commission of a crime with a firearm, assault with a weapon, injuring with intent, burglary, unlawful possession of firearms, escaping police custody and failing to stop for police.
He was remanded in custody and is next due in court on July 14.
