Looters claiming to be contractors have hit at least one tornado-damaged Hobsonville home, prompting authorities to tighten security in the area.
Cordons were set up around the Wallingford Way area after it was badly hit by Thursday's deadly tornado.
But despite the security measures, looters were able to enter the cordon zone by posing as contractors.
Civil Defence controller Clive Manley said he was aware of one such incident over the weekend, which was reported to police.
He said it was an isolated incident but it was being taken "very seriously".
"This goes on in normal life and you would hope that it would stop in these sorts of events, but unfortunately there are still people out there who do these things and they continue to do them, which is most unfortunate."
Mr Manley said security at the cordons had been tightened as a result.
"We've put more requirements around people proving they are a contractor before they are getting around," he said.
"There's an increased presence of police and security. They are basically making sure that people in properties have got some evidence that they've got a right to be there."
Three people were killed and hundreds of properties were damaged after strong winds, heavy rain and a tornado ripped through the area on Thursday.
Mr Manley said the good weather today was helping contractors and residents clean up damaged streets and properties.
"There's a lot more people back in their homes, so they're getting tarpaulins on, hauling out weather-broken glass and windows, just generally clearing.
"There's a lot of activity and we're helping people obviously as they need it."
Mr Manley said the priority was to get people back into safe homes.
Of the 150 worst hit properties, some 22 seriously damaged properties would be uninhabitable for a long time.
Some may need to be demolished, while others would need extensive repairs to the roofing and walls.
Mr Manley said some people would be out of their houses for a while, but only 29 people required emergency accommodation last night.
Power was been restored to the streets yesterday, but not all houses had been reconnected due to damage.
"There are still some properties where it's not safe to put the power to them yet until repair work has been done."
The overall cost of the damage was estimated to be $11 million.