Mafia bosses were among prisoners in L'Aquila's top-security jail transferred to other facilities in the early hours of Wednesday as aftershocks from Monday's earthquake continued to rock the Abruzzo capital.
The prison administration department decided to move the inmates at 02:00 (00:00 GMT) as a precautionary measure despite a survey revealing no structural damage to the jail.
''It was an operation without precedents carried out not so much because of structural risks to the prison but to avoid dangerous tensions among the prisoners,'' said Justice Minister Angelino Alfano.
Around 70 prison vans were required to transfer the detainees and it took 12 hours to evacuate the prison completely.
Around 140 detainees have been serving time in L'Aquila under the so-called 41-bis regime, used for Italy's most dangerous criminals to prevent them from continuing to run their affairs from their cells.
Under the tough regime inmates are kept in single-person cells and are almost entirely cut off from the outside world.
Among mafiosi serving time in L'Aquila is Salvatore Madonia, a notorious Cosa Nostra mobster serving life for the 1991 murder of Palermo businessman Libero Grassi.
Nadia Desdemona Lioce, a member of a resurgent Red Brigades terrorist group serving life for the 1999 murder of a labour ministry aide gunned down in Rome, is also a 41-bis prisoner at the jail.
Prisoners serving regular sentences were transferred to other facilities in the Abruzzo region following the evacuation, while male 41-bis prisoners were moved to Spoleto prison in Umbria and the two women under the tough regime were taken to Rome's Rebibbia jail.
