Nineteen Commonwealth Bank customers allegedly took advantage of a software glitch to steal about $217,000 from the bank as they attempted to steal up to $7m, police say.
Major fraud squad Det-Const. Jennie Ayre claimed the group had withdrawn cash from automatic teller machines in excess of the funds in their bank accounts.
It is alleged that at least one customer discovered by fluke that at times the ATMs seemed unable to determine when there was insufficient funds in an account.
The glitch occured each time the bank conducted software maintenance on its machines, allowing customers to withdraw as much as they could during those times.
The group allegedly told others of the glitch through social networking sites or phone calls, with the extra funds allegedly taken from ATMs statewide between December 2010 and March 2011.
Police say more than 30 Commonwealth customers were identified as continually accessing money from CBA ATMs to which they were not entitled.
Police charged 19 people with 197 counts of stealing.
Bank records allegedly show they tried to steal more than $7 million.
Despite the ATMs being unable to prevent the withdrawals, they were allegedly recorded on customer account records and the bank called in police when they uncovered the pattern of overdrawn accounts.
Eight of those charged are yet to appear court.