Police were called to ANZ at The Base about 12.45pm on Monday and say 'a quantity of cash” has been stolen.

It took less than 30 seconds for three men with weapons to rob security staff at a bank in northern Hamilton, a witness says.

The aggravated robbery near The Base was reported to police about 12.45pm on Monday.

A nearby shopper described seeing figures in white overalls and hoods, who had weapons right in the face of a security guard and took off with money bags.

A police spokesperson said security staff were confronted by three men with weapons who stole a quantity of cash. 'The security staff were not physically injured.”

A nearby shopper said 'the robbers were right in [a security guard's] face with a shotgun”, grabbed the money bags and took off. Photo: Supplied.

An onlooker who witnessed the robbery unfold says everything happened really fast – within 30 seconds.

The woman, who did not want to be named, was shopping next door when she saw two security guards being threatened with shotguns as they were transferring money from the armoured transport van to the bank around 1 pm.

'They [security guards] dropped the money bags; the lady ran like hell to the corner while the man started shouting for help.

'The robbers were right in his face with a shotgun, grabbed the money bags, ran into the car park and got away in a car.”

The robbers, who she thought were males, were wearing white overalls with hoods over their heads and had their face masks on, she says.

'If I had a shotgun pointed at me, I would have done the same thing and dropped the bags,” the woman says.

At the scene, an ACM armoured transport van remained parked outside the branch.

The service offers uniformed personnel 'with visible firearms”, according to the company website.

'This service is suitable for high volumes of cash and valuables.”

The offenders left in a green-coloured Subaru station wagon registration KNR252, which has since been found in Pukete. The offenders left the area in another vehicle.

At this time police are unable to comment on how much was stolen.

An area outside the ANZ branch at The Base was taped off on Monday afternoon.

The manager at IT Fox Solutions, who did not give his name, was busy with customers when he heard loud police sirens and soon the cordons sealed off the area.

For businesses at The Base, safety was a big concern with car thefts becoming increasingly common.

One of the businesses Stuff spoke to says they had received warning from The Base management to not leave anything valuable in the car.

Jo Lines-MacKenzie and Avina Vidyadharan/Stuff