"There was a young child in the front seat and the two offenders got in the back. They then forced the driver to drive them to the intersection of Wordsworth Road and Weymouth Road, Manurewa."
The men then got out and were last seen running across Weymouth Road towards Friedlanders Road, Manurewa.
"This is a particularly frightening experience for a member of the public who was inadvertently caught up in this crime," said Mr Ellwood.
"While the victim was very shaken by the experience, thankfully she was otherwise unharmed."
One of the men was wearing a black hoodie with the words "West is Best" in white writing.
Police were appealing for information about the people involved in the aggravated robbery or to anyone who saw the two offenders running through Southmall, the Manurewa Train Station area, or near the intersection of Weymouth Road and Friedlanders Road, Manurewa.
"We ask that anyone who knows these people or who might have seen a discarded till to please contact Police as soon as possible," says Detective Senior Sergeant Ellwood.
Please contact Detective Logan Pene of the Manurewa CIB on 09 213 9167 or anonymously to Crimestoppers on 0800 555 111.