N.Ireland Tensions Rise Over Bloody Sunday Probe Divisions are rising in Northern Ireland's cross-community government over police plans to open a criminal investigation into Bloody Sunday, the 1972 killing of 13 Irish Catholic demonstrators by British soldiers. The Protestant who leads the 5-year-old coalition, Peter Robinson, said Friday that police must investigate what his Catholic colleague atop the government, Martin McGuinness, was doing as an Irish Republican Army commander on that day 40 years ago. McGuinness said he would cooperate with any investigation into the Londonderry slaughter, but denied allegations he was carrying a submachine gun on Bloody Sunday and opened fire on troops. He accused Protestant leaders of undermining efforts to bring charges against retired soldiers. A 12-year fact-finding probe into Bloody Sunday concluded in 2010 that soldiers opened fire without provocation on unarmed protesters.