The Central Bank is to begin an inquiry into the conduct of certain managers at Irish Nationwide Building Society.

The inquiry follows a preliminary investigation where the bank says certain actions taken by senior managers may have contravened some banking rules.

The bank has not outlined the suspected breaches, and has not said exactly which managers will now face an inquiry.

However any finding against senior managers could result in a fine of €1 million for each of them.

Irish Nationwide was merged with Anglo Irish Bank in 2011 to form IBRC, which was put into liquidation into 2013.