The 1867 rebellion of the Irish Republican Brotherhood (IRB) was the culmination of several years of agitation by this secret, oath-bound organisation. The IRB, or Fenians, planned a national insurrection and the foundation of an Irish Republic with the aid of radicalised Irish units in the British Army. Although the Fenians had some success in infiltrating army units and had a considerable presence in parts of Ireland, the British took steps to remove seditious army units from Ireland and the rebellion was launched against the better judgement of the IRB leadership on the urgings of the American-based Fenian Brotherhood. It was unsuccessful in a military sense with only isolated skirmishes taking place but did become a focal point in Irish revolutionary folklore, inspiring later generations of rebels. Clan na Gael later conducted several bombing attacks in England and attempted to free their imprisoned allies. One such raid resulted in the hanging of three IRB men, known as the "Manchester Martyrs", for the killing of a policeman.