The region remained under Chinese control intermittently, and when China was weak in the Western Regions, Loulan was essentially independent. In 25 CE it was recorded that Loulan was in league with the Xiongnu. In 73 CE, the Han army officer Ban Chao went with a small group of followers to Shanshan, which was also receiving a delegation from the Xiongnu at the same time. Ban Chao killed the Xiongnu envoys and presented their heads to the King, after which King Guang of Shanshan submitted to Han authority. This would ensure the first step of the 'Silk Road' from central China to Shanshan would be under stable Chinese control. Around 119, Ban Yong recommended that a Chinese colony of 500 men be established in Loulan. A later military colony was established at Loulan by General Suo Man. It was recorded that in 222 CE, Shanshan sent tribute to China, and that in 283, the son of the king was sent as a hostage to the Chinese court during the reign of Emperor Wu of Jin. Loulan was also recorded as a dependent kingdom of Shanshan in the 3rd century "Book of Wei".