A homicide inquiry has been launched after a partygoer died inside a Manurewa nightclub in the early hours.
Police say a male patron died at Club 220 on Great South Road shortly after 3am.
Nightclub staff were giving the 30-year-old man CPR when emergency services arrived. However, he died soon after.
Police say a 28-year-old man has been arrested and charged with assault. He will appear in Manukau District court on Monday.
Staff and patrons from the club are assisting police with their investigations, officers say. Enquiries are continuing to identify the deceased and advise his family.
The death comes during a "night from hell" for Counties Manukau police who struggled to cope with the high volume of calls.
Counties Manukau senior sergeant John Yearbury said: "There was a lot of disorder and domestic incidents across the district - more than usual for a Friday night.
"There was lots of fighting, and groups of people fighting in the streets of various locations over town - Otahuhu, Mangere, and Manurewa - so much so that we couldn't keep up. We're still mopping up now."
Senior sergeant Yearbury also confirmed the Club 220 incident.
He said: "There was a death in Manurewa which we are treating as a homicide at present.
"At a bit after 3am at Club 220 on Great South Road we were called to the fact that a male patron, about 30, was being given CPR by staff.
"When we arrived we continued with the CPR with the assistance of ambulance but he died at the scene.
"We're still in the throes of finding out just what's gone on there."
A St Johns spokeswoman said: "We were requested to attend a bar in Manurewa by police at 3.10am. A guy was unconscious before going into cardiac arrest. He was declared deceased at the scene at 3.20am."