Negotiations saw the establishment of a Boundary Commission to reconsider the border between Northern Ireland and the south, the possibility of the 26 counties being given status as a "free state" and the requirement of an Oath of Allegiance for all Irishmen. Both Craig and Carson vehemently opposed the Boundary Commission, fearing it would greatly diminish the existing area of Northern Ireland (in the end, the border hardly changed at all). The truce had little effect in the north as violence peaked in the first half of 1922, after the Anglo-Irish Treaty confirmed the partition of Ireland into Northern Ireland and the Irish Free State. Michael Collins, a leader in the Republican movement and commander of the IRA, covertly sent arms and aid to the northern IRA with the aim both of defending the Catholic population there and sabotaging the government of Northern Ireland in hopes of its collapse. Loyalists recognized the IRA's tactic of subversion and openly attacked Catholic neighbourhoods, which were somewhat defended by IRA gunmen. Roughly thirty people were killed in Belfast in February 1922, sixty in March and another 30 in April. Recurring cycles of violence continued until the summer of 1922. In response to this most recent conflict, the First Dáil imposed a boycott on goods produced in Belfast from 6 August 1920, which proved to be ineffective.