As the Irish Government confirmed some weeks ago, the top MI5 mole in the provisional IRA during the latter years of the “troubles” in Northern Ireland was Freddie Scapaticci, nicknamed Stakeknife. There is presumably good reason why the “Republican Movement” has never confirmed this, given the reported seniority of Scapaticci inside the IRA.
He was, after all, that organisation’s head of security, and feeding information on the IRA to the British Government.