 Mehmed refused and met Mustafa's forces in battle, easily defeating them.Mustafa escaped to the Byzantine city of Thessaloniki, but after an agreement with Mehmed, the Byzantine emperor Manuel II Palaiologos exiled Mustafa to the island of Lemnos.However, Mehmed still faced some problems, first being the problem of his nephew Orhan, who Mehmed perceived as a threat to his rule, much like his late brothers had been.