The plan called for units of specially trained and equipped Irish commandos to infiltrate Northern Ireland and launch guerilla-style operations against the Belfast docks, Aldergrove airport, the BBC studios and key industries. The campaign would start in Belfast and the northwest, so as to draw the bulk of security forces in Northern Ireland away from the border areas and turn their attention to the guerilla campaign. The Irish Army would then invade with four brigades operating in company-strength units to occupy the Catholic areas of Derry and Newry, and attack any remaining security forces in those areas.