Lambert and Brenda Shapiro Glenn were moving boxes from Shapiro Glenn's Jeep to an office in Mt Wellington when a man stole two bags from the unlocked car around 11am.
Lambert saw the man out of the corner of her eye and shouted at him as he was trying to steal a power tool from the car's boot.
He dropped the tool and ran off down the street with the bags.
"I chased after him and then remembered I was pregnant so I probably shouldn't be running," Lambert said.
Shapiro Glenn immediately called police and Lambert was able to provide the make, model and registration plate of his car, and a description of the culprit.
"I thought maybe they would even finger print the vehicle. [But] nobody came out to see us," Lambert said.
Screenshots of a possible location for the thief, based on information from a tracking device on Shapiro Glenn's iPhone were also later sent to police.
On Thursday, Shapiro Glenn called police and was told no progress had been made. "Until [Friday] it hadn't been assigned to a police officer, I was told," she said.
Shapiro Glenn said she knew police were busy but she wanted her belongings back.
A police spokeswoman said the Counties Manukau Investigation Support Unit were looking into the incident.
Officers had tried to contact one of the women on Friday but had been unable to reach her.
A spokeswoman said the location from where the stolen iPhone was "polling" only gave a general area, and not a specific address.
Checks have been made into the registration plate provided by the victims to police. The car was registered to an owner in Stoke, Nelson.
"Enquiries are ongoing into the registered owner of the car registration plate that the owner provided, and this includes enquiries at the address as Nelson, as well as previous addresses."
The spokeswoman said if a member of the public calls and a suspect is still present, every attempt will be made to assign a patrol immediately if one is available.
"The time taken between a job being dispatched and officers attending can be dependent on the distance of any available patrol to the scene and even traffic and whether or not the offender is still there."