sentences:  It became known as the "Christmas Massacre" (Strage di Natale) and was initially attributed to political extremists.It was only several years later, when police stumbled on explosives of the same type as used in Train 904 while searching the hideout of Giuseppe Calò, that it became apparent that the Mafia had been behind the attack.As part of the Maxi Trial, Riina was given two life sentences "in absentia".