China says won't tolerate national security threats in Hong Kong

China won't tolerate challenges to the bottom line of the "one country, two systems" formula that governs Hong Kong, separatism or threats to national security there, a senior Chinese official said on Friday after a meeting of the top leadership. The past five-months of anti-government protests in the former British colony represents the biggest popular challenge to President Xi Jinping's government since he took over the leadership in late 2012.