This was common practice on a smaller scale for the IRA (Provisional IRA, etc.) throughout the Troubles from what I understand, though the heist you're referrin

This was common practice on a smaller scale for the IRA (Provisional IRA, etc.) throughout the Troubles from what I understand, though the heist you're referring to is particularly notable due to its magnitude and later timing. It evidently proved to be a relatively easy way to raise money, especially as it was at the loss of their purported enemy.