 Complete the following phrase:  After the arrest of Mafia boss Totò Riina in January 1993, the remaining bosses, among them Giuseppe Graviano, Matteo Messina Denaro, Giovanni Brusca, Leoluca Bagarella, Antonino Gioè and Gioacchino La Barbera came together a few times often in the Santa Flavia area in Bagheria, on an estate owned by the mafioso Leonardo Greco. They decided on a strategy to force the Italian state to retreat. That resulted in a series of bomb attacks in 1993 in the 