Bank of Ireland has apologised after a glitch led to some of its customers withdrawing or transferring more money than was in their accounts.

The bank said this was down to a technical issue with its services and not a cyber attack.

Bank of Ireland said its app and and online services are working again on Wednesday and any transfers or withdrawals taken out during the outage will appear in their accounts during the day.

It has informed customers who withdrew more cash than was in their accounts that this would appear as an overdraft, and encouraged those who find themselves in financial difficulty as a result of the fault to get in touch.

It comes after large queues built up at the bank’s ATMs in parts of the country on Tuesday and messages on social media encouraged people to withdraw cash despite not having funds in their accounts.

An Garda Siochana said it was aware of an “unusual volume of activity” at some ATMs across the country.

In a statement on Wednesday, the bank said: “Yesterday a technical issue impacted a number of Bank of Ireland’s services.

“Our teams restored these services overnight and all services are available to customers this morning. Overnight payments to accounts may appear throughout the day.

“We are aware that the technical issue meant some customers were able to withdraw or transfer funds above their normal limits.

We are engaging with Bank of Ireland to ensure that any issues and errors identified are resolved for customers

“These transfers and withdrawals will be applied to customers’ accounts today. We urge any customer who may find themselves in financial difficulty due to overdrawing on their account to contact us.

“We sincerely apologise for the disruption this outage caused – we know we fell far below the standards our customers expect from us.”

Bank of Ireland was fined 24.5 million euro (about £21 million) in 2021 by the Central Bank of Ireland over failures to have a robust framework to ensure continuity of services in the event of a significant IT disruption.

Asked about the outage on Tuesday, a spokesman for the Central Bank said it “continues to monitor the situation regarding the availability of certain services provided by Bank of Ireland”.

“We are engaging with Bank of Ireland to ensure that any issues and errors identified are resolved for customers, and that it is doing all it can to ensure customers’ expectation of a high-quality, uninterrupted service is met.

“Customers should contact Bank of Ireland in the first instance if they have concerns about their service.

“For more information, impacted customers should contact Bank of Ireland on is 0818 214 365 or visit www.bankofireland.com.”