A second person has appeared in court over a firearms incident at Middlemore Hospital earlier this month.
An investigation has been ongoing since 4 January, when a firearm was allegedly fired from a vehicle.
Detective Inspector Shaun Vickers says the Counties Manukau Offender Prevention Team executed a search warrant late last week.
"At a Manurewa address, a 23-year-old man was located by our staff and arrested," he says.
"The investigation team have laid a number of serious charges against this man."
He has been charged with committing a dangerous act with intent to cause grievous bodily harm, and commission of an offense with a firearm.
The 23-year-old appeared in the Manukau District Court over the weekend and will reappear today.
Two arrests have now been made in the investigation.
Police are not ruling out further arrests or charges being made, Detective Inspector Vickers says.
