A brazen thief has pinched a car from an Auckland mum while she stood just centimetres away holding her baby and helping her other young son put on his gumboots.

Jana McMiken was moments away from strapping her wee boys into their car seats when the daring theft happened in a Northpark carpark last Friday afternoon.

The keys were in the ignition of her Toyota Corolla because she had wound down the windows to let in some cool air and had been packing the car, she said.

She was standing just in front of the car coaxing three-year-old Billy into gumboots - one boot sitting on top of the bonnet - when she heard a car turn on.

McMiken turned around horrified to see her own Toyota Corolla pulling away from her.

The life-long Waiheke Island resident had been staying in Auckland for the week meaning all her personal belongings were in the car: toiletries, make-up and clothing plus everything she needed to take care of her boys.

The ErgoBaby carrier, portacot and much adored bed-time bear were all gone, she said.

"Every possible thing that you could ever think you could need," she said.

"I was just left with a gumboot and my kids.

"Imagine if he had drove off with them in the car?

"That would have been worse than hell."

Still holding one-year-old Beauden she ran towards the white car and banged on the back window.

"I was panicking. I couldn't do anything. I felt completely hopeless."

Auckland woman Jana McMiken is appealing to the public for sightings of her stolen white 2012 Toyota Corolla which has the licence plate GLS745. Photo / Supplied

Most people seemed slow to catch on that the car was being stolen, she said.

"Everybody looked at me like I was crazy - I think they thought I was having a fight with my boyfriend."

He was beeping the horn and telling people to move out of his way, she said.

The thief then drove the wrong way around the roundabout to make a quick exit, she said.

One person offered to drive her around in a bid to follow the stolen car, but without car-seats she simply did not feel like she could go.

"It was strange," she said.

"It doesn't feel like stuff like that happens in New Zealand?"

McMiken wanted to share her story to warn others to be careful.

Stranded without a phone or wallet, a friend she was with dropped her off at the ferry where between tears she begged to be let on so she could get home to her husband.

The days since had been a struggle - she has found a car she can borrow for a couple of weeks but will soon again be left without.

"Having no car on Waiheke is pretty impossible with kids."

McMiken only had third-party insurance so had no cover for what happened.

She lost more than $20,000 worth of property and is appealing to the public for any sightings of her stolen car.

Counties Manukau East Police Inspector Chris Barry said police are investigating the incident.

Barry said about 3pm, the woman had been standing near her vehicle in a carpark on Ti Rakau Drive when an unknown offender has gotten into the car and driven off.

The stolen vehicle – a white Toyota Corolla, registration GLS745 – has not been located, he said.

"This incident unfortunately serves as a reminder that there are opportunistic offenders out there and we ask the public to always be aware of their surroundings and be on the lookout for any suspicious behaviour, particularly in public areas such as carparks.

"In general we ask the public to never leave valuables or belongings in vehicles and ensure their vehicle is always locked when unattended.

"We ask anyone who witnesses suspicious behaviour to contact police immediately."

Anyone with information about this incident or any sightings of the Toyota Corolla is asked to contact Ormiston Police on 09 250 2800, or Crimestoppers anonymously on 0800 555 111.