 Complete the following phrase:  In 1931, following the Japanese invasion of Manchuria, he was forced to retreat to Jinzhou, where he became commanding general of the remts of the Fengtian forces of the Northeastern Border Defence Command. After their defeat he became a member of the Peking Branch, National Military Council, in 1933. He was commander of the Chinese 6th Army Group 2nd Northern China Army Group during the 