Jochi played a major role in the Khwarezm war of 1219–1221 in Central Asia – his forces captured the towns of Signak, Jand, and Yanikant in April, 1220, during this war. Subsequently, he was given the command of operation against the city of Urgench (Gurganj, in present-day Turkmenistan), the capital of the Khwarezmian Empire. Here the siege of the town suffered delays because Jochi engaged in extensive negotiation with the town to persuade it to surrender peacefully and to save it from destruction. Jochi's brother Chagatai regarded this action as militarily unsound: Chagatai wanted to destroy the city but Genghis Khan had promised the city to Jochi after his victory. This difference of opinion on military affairs deepened a rift between Jochi and Chagatai. Genghis Khan intervened in the campaign and appointed Ögedei as the commander of the operation. Ögedei resumed the operations vigorously – capturing, sacking and thoroughly destroying the town and massacring its inhabitants (1221).