March 21, 2002 Red Brigades Say They 'Executed' Italy Official By REUTERS Filed at 3:35 p.m. ETROME (Reuters) - An offshoot of Italy's Red Brigades urban guerrilla movement published a 26-page Internet message on Thursday saying it had ``executed'' a top government adviser and reviving fears of a new era in political killings.Marco Biagi, 52, was shot dead on Tuesday night in the northern city of Bologna with the same pistol that the Red Brigades for the Construction of the Fighting Communist Party had used to kill another government aide in 1999.Police pored over video material collected from security...