Using his control of the Anatolian shore of the Marmara Sea, Abu'l-Qasim decided to build a navy at Kios and challenge the Byzantine navy. The Byzantine emperor Alexios I Komnenos sent two of his generals, Manuel Boutoumites and Tatikios, against him. Abu'l-Qasim's army was defeated, his fleet destroyed, and he himself was forced to retreat to Nicaea, from where he concluded a truce with the emperor (see Seljuk campaigns in the Aegean).