Over the space of two months, a skimming device inserted into an ANZ bank ATM on the corner of Elizabeth and Collins Streets in the Melbourne CBD was used by the theives to record user card details.
The thieves would later use these details to access funds from customer accounts.
Victoria Police have CCTV footage of two individuals they believe to be responsible.
One is a man of around 170cm tall, unshaven with olive skin, dressed in a black peaked cap, dark blue jumper, blue jeans and white sneakers, carrying a black and grey Reebok-branded backpack.
The other is 180cm tall with fair skin, wearing a white peaked cap, black jacket, blue jeans and white sneakers, carrying a multi-coloured shoulder bag.
Victoria Police believe the two may be a part of an international crime syndicate.
Any information related to the theft can be reported to Crime Stoppers on 1800 333 000.