In an update about 10pm, they said the person had now been transferred to Waitākere Hospital by ambulance.
The incident occurred near Lion Rock.
Police have been approached for comment.
Day of water tragedies
The incidents today occurred in Canterbury, Bay of Plenty, Waikato and Mahurangi East, north of Auckland.
Another person is in a serious condition after being pulled from the water in Tasman District.
The incidents come amid a slew of heat warnings today, with temperatures hitting the 30s in some regions, drawing thousands of Kiwis to rivers and beaches.
A person died after a water incident at a popular Canterbury tourist spot this afternoon.
Police were notified about 1.15pm that a person had been pulled from the water by the harbourmaster at Akaroa on Banks Peninsula.
Meanwhile, police said emergency services were called about 2.55pm to a location off Poripori Rd in the Bay of Plenty, where a person had been pulled from the water.
“CPR was commenced, however they sadly died at the scene. The death will be referred to the coroner.”
A man is also missing after a water-related incident in the Waikato River this afternoon.
Police were called to the river near Graham Island, in Hamilton, about 3.30pm after a report of a struggling swimmer being swept downstream.
Water safety advice
Water Safety New Zealand chief executive, Glen Scanlon, urged people to keep in mind the key messages around water safety at this busy time.
“What we tend to see is so often those hot, calm days when people find themselves unexpectedly in more trouble because the conditions look so good,” Scanlon said.
He advised Kiwis to never swim or dive alone in any of New Zealand’s water environments.
“If you’re at a patrolled beach, please swim between the flags. Take advantage of the great surf lifesavers and the job they do to keep you safe.
“Please, if you’re fishing from land or from a boat as well, wear a life jacket. It’s going to keep you really super safe.
“If you’ve got your kids, always stay close to them,” Scanlon said.
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