The Central Bank has said it is working to establish 'a full account' of an incident at Bank of Ireland.
It comes after queues formed at ATMs on Tuesday night, after a technical glitch meant people reported seeing money in their Bank of Ireland accounts they did not have before.
Gardaí were also brought in to disperse the queues and the bank has insisted extra funds “will be debited from [customers’] account[s]” in the future.
Bank of Ireland has apologised to customers for any confusion and inconvenience. The incident has made international headlines around the world.
In a statement, the Central Bank has said it is monitoring the situation.
"When system outages occur that impact the financial system, the Central Bank of Ireland will engage to establish a full account of the incident," it said.
"We have begun that process with Bank of Ireland as it works to resolve these issues and restore services for customers."
The Central Bank said this process would likely include "understanding the root cause of the recent service disruption and what BOI is doing to avoid further disruption for BOI customers".
"We are monitoring the situation and will continue detailed supervisory engagement, but are not in a position to release confidential supervisory information regarding any institution."
It said where issues do occur, Bank of Ireland should "rectify the issues urgently".
"We require banks to put things right where they have made errors or cause customer harm," it added.
Customers are advised to contact Bank of Ireland in the first instance if they have concerns about their service on 0818-214-365.