Throughout the early months of 1922, Collins had been sending IRA units to the border and sending arms and money to the northern units of the IRA. Collins joined other IRB and IRA leadership in developing secret plans to launch a clandestine guerrilla war in the northeast. Some British arms that had been supplied to the Provisional government in Dublin were turned over by Collins to IRA units in the north. In May–June 1922 Collins and IRA Chief of Staff Liam Lynch organised an offensive that would involve mobilising and arming "both" pro- and anti-Treaty IRA units along the border area. Because of this, most northern IRA units supported Collins and 524 individual volunteers came south to join the National Army in the Irish Civil War.