Protesters demonstrate outside the Japanese embassy in Beijing on Sept 18.FENG YONGBIN / CHINA DAILY

Soldiers take an oath in front of a monument with Chinese characters "Don't Forget the National Humiliation" on it as a way to commemorate the 81st anniversary of the "Sept 18 Incident," which directly preceded Japan's invasion of northeast China, in Changshu City, East China's Jiangsu province, Sept 18, 2012. On Sept 18, 1931, Japanese troops blew up a section of the railway under its control near Shenyang, then accused Chinese troops of sabotage as a pretext for war. They bombarded the barracks of Chinese troops near Shenyang the same evening, thus starting a large-scale armed invasion of northeast China. [Photo/Xinhua]