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. (December 2017)
The Rus' and their allies, the Pechenegs, disembarked on the northern coast of Asia Minor and swarmed over Bithynia in May 941. As usual, they seemed to have been well informed that the Imperial capital stood defenseless and vulnerable to attack: the Byzantine fleet had been engaged against the Arabs in the Mediterranean, while the bulk of the Imperial army had been stationed along the eastern borders.
Lecapenus arranged a defense of Constantinople by having 15 retired ships fitted out with throwers of Greek fire fore and aft. Igor, wishing to capture these Greek vessels and their crews but unaware of the fire-throwers, had his fleet surround them. Then, at an instant, the Greek-fire was hurled through tubes upon the Rus' and their allies; Liudprand of Cremona wrote: "The Rus', seeing the flames, jumped overboard, preferring water to fire. Some sank, weighed down by the weight of their breastplates and helmets; others caught fire." The captured Rus' were beheaded.
The Byzantines thus managed to dispel the Rus' fleet but not to prevent the pagans from pillaging the hinterland of Constantinople, venturing as far south as Nicomedia. Many atrocities were reported: the Rus' were said to have crucified their victims and to have driven nails into their heads.
In September, John Kourkouas and Bardas Phokas, two leading generals, speedily returned to the capital, anxious to repel the invaders. The Kievans promptly transferred their operations to Thrace, moving their fleet there. When they were about to retreat, laden with trophies, the Byzantine navy under Theophanes fell upon them. Greek sources report that the Rus' lost their whole fleet in this surprise attack, so that only a handful of boats returned to their bases in the Crimea. The captured prisoners were taken to the capital and beheaded. Khazar sources add that the Rus' leader managed to escape to the Caspian Sea, where he met his death fighting the Arabs.