Bank of Ireland has confirmed that four laptops containing personal information on 10,000 customers have been stolen.
The disclosure came after the Data Protection Commissioner, Billy Hawkes told RTÉ News tonight that he is investigating the disappearance of the laptops.
The notebooks held sensitive information such as customers' names, addresses and bank account details
The laptops, which were reportedly stolen last year, were used by employees working for the bank's life asssurance division.
Mr Hawkes told RTE News that he had only been made aware of the issue on Friday and was investigating the data theft as a matter of urgency.
In February, the Data Protection Commissioner's office was forced to investigate the loss of a laptop which had data on more than 171,000 Irish blood donors after the Irish Blood Transfusion Service (IBTS) admitted that a notebook had been stolen.