Emperor Taiwu made the first major attack of Feng Hong's reign, heading for Northern Yan's capital Helong (和龍, in modern Jinzhou, Liaoning). Feng Hong tried to appease the Northern Wei emperor by delivering gifts of beef and wine to his army, to no avail. 10 Northern Yan commanderies surrendered to Northern Wei, and Northern Wei forces captured a number of Northern Yan cities and put Helong under siege. However, two months later, Emperor Taiwu withdrew after capturing 30,000 households from Northern Yan and relocating them to his You Province (幽州, modern Beijing, Tianjin, and northern Hebei). Feng Hong's official Guo Yuan (郭淵) suggested to Feng Hong that he offer to be a Northern Wei vassal and send a daughter to be Emperor Taiwu's consort, but Feng Hong refused, stating that the enmity between the states were so deep that he would be killed anyway even if he surrendered. (While Northern Wei was sieging Helong, the Northern Wei general Zhu Xiuzhi (朱脩之), who had been captured from Liu Song, plotted to assassinate Emperor Taiwu and then join Feng Hong, but his plot was discovered, and he fled to Feng Hong, who in turn sent him back to Liu Song, seeking Liu Song aid. Henceforth, Liu Song and Northern Yan were informal allies, although Liu Song provided little actual help.) Around the new year 433, Feng Lang and Feng Miao, believing that Northern Yan was on the verge of destruction and believing that Princess Murong was planning to have them killed, fled to Liaoxi (遼西, in modern Tangshan, Hebei), where Feng Hong had sent their older brother Feng Chong to be the commanding general of. They persuaded Feng Chong to surrender to Northern Wei, and Feng Chong sent Feng Miao to Northern Wei to offer his allegiance. Feng Hong, in response, sent his general Feng Yu (封羽) to put Liaoxi under siege. In spring 433, Emperor Taiwu sent his younger brother Tuoba Jian (拓拔健) the Prince of Yongchang to relieve Liaoxi, and further created Feng Chong the Prince of Liaoxi with a number of other honors, to try to encourage other defectors. Tuoba Jian's forces soon surrounded Feng Yu and forced his surrender, and then withdrew with 3,000 captive households. Feng Chong then requested permission to go to Helong to persuade Feng Hong to surrender, but Emperor Taiwu did not grant such permission. In spring 434, Feng Hong sent messengers to Northern