Japan warns China over 'territorial aggression'

China risks triggering unintended conflict with Asian rivals through its aggressive stance in maritime disputes, Japan said Tuesday in a security assessment, as a Beijing minister urged preparations for a "people's war at sea". China's sweeping claims over the South China Sea, where it has built a series of artificial islands capable of supporting military operations despite overlapping claims from other nations, have stoked international alarm. The region's superpower "continues to act in an assertive manner" and its actions "include dangerous acts that could cause unintended consequences", Tokyo said in a defence white paper.