RTÉ News reports:
Permanent TSB has confirmed it has reported a data breach to the Data Protection Commissioner.
The bank said the breach involved account information relating to less than 100 customers being mistakenly emailed to an unrelated customer.
It is also believed that notes of meetings customers had with bank staff were also included.
It is thought some of these customers were those affected by the recent overcharging controversy.
The bank said the email contained the account number and the names of the customers who held that account together with some other material.
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