Patons Place Jewellers inside the Craigieburn Central shopping centre was targeted by two armed men, using metal poles to shatter cabinets and steal jewellery.
Shoppers reportedly ran and hid inside other stores, while businesses shut their roller doors. The raid ended in less than one minute after a staff member chased the thieves with a ring-sizing stick.
Victoria Police Detective Sergeant Adam Foley noted the courage of the staff member in confronting the suspects.
"It's pretty disgusting that they can walk into a busy shopping centre on a Sunday morning and cause panic and hate, havoc to people who are just going about their normal business," he told 9News.
"They're a bit shaken up, but obviously one of them was also rather brave in that they chased one of the offenders out.”
Investigators are searching for a dark-coloured Mazda CX5 that was used as a getaway vehicle by the four suspects.
Anyone with information is urged to contact Crime Stoppers on 1800 333 000.
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