Soldiers sign their names on a banner to express their courage to defend the territory of the motherland in south China's coastal province Fujian Sept.18,2004. It is also the 73rd anniversary of the start of Japan's invasion of China, known as the Mukden Incident occurred on Sept.18,1931, when Japanese troops began occupying northeast China.To remind the Chinese people of the national humiliation, Sept. 18 was decided as the Day to mark the incident.