DUBLIN, Republic of Ireland (AP) -- A former senior official of Sinn Fein recently exposed as a British spy has been found fatally shot in northwest Ireland, police said Tuesday -- an act certain to send shock waves through Northern Ireland's peace process at a critical moment. Denis Donaldson, Sinn Fein's former legislative chief in the failed power-sharing government of Northern Ireland, admitted in December he had been on the payroll of the British secret service and the province's anti-terrorist police for the previous two decades. He then went into hiding -- because the traditional Irish Republican Army punishment for...