In early 1765, a 20,000-strong Burmese army stationed at Kengtung, led by General Ne Myo Thihapate, left Kengtung for yet another Burmese invasion of Siam. With the main Burmese army gone, Liu used a few minor trade disputes between local Chinese and Burmese merchants as the excuse to order an invasion of Kengtung in December 1765. The invasion force, which consisted of 3,500 Green Standard troops along with Tai-Shan militias, laid siege to Kengtung but could not match battle-hardened Burmese troops at the Kengtung garrison, led by Gen. Ne Myo Sithu. The Burmese lifted the siege and pursued the invaders into Pu'er Prefecture, and defeated them there. Ne Myo Sithu left a reinforced garrison, and returned to Ava in April 1766.