Scores of customers descended on an Alliance & Leicester ATM in Scotland after word spread that the unit was dispensing double the amount of cash requested.
According to local newspaper The Daily Record, people flocked to the cash machine at a petrol station in Ardrossan, Ayrshire, after it began issuing £20 for every £10 withdrawn.
Although the free cash bonanza only lasted around 30 minutes before the bank took the unit offline, thousands of pounds was withdrawn, says the Record.
Maggie Campbell, who works at the station, told the paper that her suspicions were aroused when she noticed the same people kept returning to the machine and then began making calls on their mobile phones.
Within minutes a queue of around 60 people had built up as customers looked to cash in on the malfunction, with one man reportedly landing £3000 when he withdrew all the money on his debit and credit cards.
A&L told the Record it is investigating the incident and customers may be asked to return the money.
In March hundreds of people flocked to a faulty Payzone ATM in the UK city of Hull after it started dispensing twice the amount of cash keyed in for withdrawals.