The accounts were struck by an international skimming gang, who specialize in ATM fraud, according to a report in the daily tabloid Heute on Friday.
Police believe that the same gang struck accounts in Krems in May, also in Lower Austria.
Skimming is a sophisticated fraud technique which involves placing a second keyboard over the existing keyboard of the bank's ATM (known locally as a Bankomat). Additionally, a magnetic strip reader is placed in front of the card slot.
The combination of keyboard capture and strip reading means that both the account number and PIN are stolen by the scammer.
Once the information is obtained, it's used to create fake cards, which are taken to ATMs in Vietnam, where cash is withdrawn from the accounts via the international banking network.