The fall of Syracuse seemed to clear the way for an Aghlabid invasion of the Italian mainland, on which the Aghlabids already had a foothold. But the Aghlabid navy, which had plied the Mediterranean practically unopposed for much of the century, soon faced its first serious disaster. In 880, a Byzantine fleet assembled by Emperor Basil I, under the command of the "droungarios" Nasar, trapped and destroyed the Aghlabid fleet at the naval Battle of Cephalonia off western Greece. With the sea cleared, the Byzantines went on the offensive on the south Italian mainland and captured the Muslim holdings in Apulia and Calabria, notably seizing the citadel of Taranto, which had been captured by the Aghlabids forty years earlier. Streams of Muslim refugees fled the Greek onslaught towards the western Campania coast, where they were received by Bishop-Duke Athanasius of Naples and resettled in pockets at Vesuvius, Agropoli and Garigliano, and even as far inland as Sepiano (near Bojano).