Detective Senior Constable Joshua Paroci (31) died while on a commercial trip on Shotover River, through Skippers Canyon, with Challenge Rafting.
He joined New South Wales Police Force in 2008 and was most recently working at the State Crime Command's Child Abuse and Sex Crimes Squad.
Squad Commander, Detective Superintendent John Kerlatec, yesterday said Det Snr Const Paroci was ``a great man and an excellent detective, and will be sorely missed by the team''.
``Professionally, Josh was a tireless worker; dedicated to investigating some of the most heinous crimes against children,'' Det Supt Kerlatec said.
``His passion was justice for victims. Not only was he a police officer, he was completing a law degree, which he intended to use to create better outcomes for young victims.
``Josh was inspirational, and everywhere he worked, he turned colleagues into mates. Today, we mourn the loss of our good mate.''
Det Snr Const Paroci's family requested privacy.
NSW police commissioner Mick Fuller yesterday extended condolences to them on behalf of the force.
``The hardest part of my job is when we lose one of our own and my thoughts are with Det Snr Const Paroci's wife, who is also a police officer, family, friends and colleagues.
``Det Snr Const Paroci was well respected by all those who knew him and the police family will rally around his loved ones during this difficult time.''
New Zealand Police continue to make inquiries on behalf of the coroner, and with the assistance of Maritime NZ, which is conducting its own investigation into what happened.
A postmortem was due to be held in Invercargill yesterday.
Det Snr Const Paroci was on a commercial whitewater rafting trip on the Shotover River with Challenge Rafting.
He died on the same stretch of Shotover River rapids where rafting guide Keith ``Chief'' Haare died due to a medical event just two months ago.
The raft overturned on the `Toilet' section of rapids about 3.45pm. Det Snr Const Paroci was in the raft with five other Australians and a rafting guide. There were two other rafts on the trip, along with safety kayakers.
A statement from the company on Sunday said he was being brought back from the far side of the river using a rescue rope after the raft flipped, but he lost his grip.
``He was swept through the next rapid where he was met by the safety kayaker, who helped him navigate the subsequent rapid before assisting him to the shore,'' the Challenge Rafting statement said.
``He became unresponsive, CPR was provided and a defibrillator utilised. The guest received further treatment from paramedics who arrived by helicopter just after 5pm but was unable to be resuscitated.''
He was pronounced dead at the scene.