The cyclone hit the uppermost region of the North Island on Sunday and tracked down the east coast, causing widespread devastation.
Police on Saturday were investigating a possible cyclone-related death of a person in the hard-hit Hawke's Bay region, taking the death toll to nine.
Getting aid to impacted communities was also a priority, with the Navy saying a ship with 26 tonnes of supplies was on its way to Napier, in Hawke's Bay.
The Air Force said helicopters loaded with food and water were bound for the stranded village of Tutira, about 105 kilometres further north.
Prime Minister Chris Hipkins said the response to the crisis was "still under way and there are people across the North Island working around the clock".
Hipkins on Friday called Gabrielle the biggest natural disaster to hit NZ this century, and warned the death toll was likely to rise as crews made contact with hundreds of cut-off communities.
Almost 5000 people as of Friday night were registered with police as being out of touch with friends or family since the cyclone hit, authorities said on Saturday, while 885 people had registered as safe.
There were grave fears for about 10 of those still missing.
Authorities said about 62,000 households were without power nationwide. Of those, almost 40,000 were in Hawke's Bay, out of a population of about 170,000.
Nearly 2000 people remained in evacuation centres in Hawke's Bay, while potentially up to 1000 people in the region were beyond the reach of emergency services, the New Zealand Herald reported.
"We have our work cut out for us. We're focused on securing a reliable water supply, reaching isolated people and re-establishing phone and internet connections," said Ben Green, Civil Defence group controller at Tairawhiti Gisborne, north of Hawke's Bay.
4°C