"We went to have a look and she wasn't in my building. She was actually in the TAB building, just over where the car was parked.''
Cullen said as he walked the little girl over to the TAB, he heard a baby's screams coming from a nearby vehicle.
A few members of the public had also stopped to look into the car, where they could see a baby he guessed was about five months old.
"The baby was screaming...[The mother had] left the car unlocked but the windows up. One of the ladies had opened the door.
"I don't know how long [the baby] was there for, but he was screaming pretty loud,'' he said.
"We were just trying to hunt down the mother or the father and we found the mother playing pokies in there.''
Cullen said they were worried for the child, given the current heatwave spreading throughout the country.
The temperature high in Tauranga today is 25C.
He told the woman she needed to leave the machines and take her kids home.
The woman, he said, became defensive.
"I was like: 'You need to be out of here right now. You've got your kids in the car'.
"They do the usual thing where they get a bit staunch and all that and words go flying. She was like: 'The father's out there!'
"I said: 'There's no father out here, there's no one out here. It's just you, I can only see you.
"Then she got in the car and took off with the kids before the cops turned up.''
Today's incident comes after a number of recent cases where children have been left in hot vehicles as their parents were out shopping.
An Auckland man alerted security staff at the Pak'nSave in Silverdale yesterday after spotting a toddler in a locked vehicle.
On Monday, a woman shopping in Napier found a child distressed and sweating profusely, still locked into their car seat, after being left in a locked hot car in 33C heat while their mother was inside shopping.