Ts'ao Ts'ao became enraged when he heard that Chou Yu had torn his letter into pieces and killed his messenger.He ordered Generals Ts'ai Mao and Chang Yun,who had surrendered to him after the fall of Chingchou City,to lead the advance fleet,and Ts'ao Ts'ao himself led the rear fleet against Chou Yu's attack.As the two enemy fleets got closer and closer to each other,Ts'ai Mao's younger brother Ts'ai Hsun decided to attack General Kan Ning of the Wu Kingdom navy.Kan Ning shot down Ts'ai Hsun with an arrow and Kan Ning's sailors began shooting with their crossbows.