 It was said that at that time, with the imperial government being extremely weak, the warlords were refusing to submit tributes to it, but the Zhao brothers did so yearly.In 904, Zhao sent an army to head upstream on the Yangtze River to attack Kui Prefecture (夔州, in modern Chongqing), then belonging to Wang Jian the military governor of Xichuan Circuit (西川, headquartered in modern Chengdu, Sichuan).His attack was repelled by Wang's adoptive son Wang Zongruan (王宗阮), and Wang's general Zhang Wu (張武) subsequently built a large iron chain across the Yangtze, apparently to ward off another attack by Zhao.