Xi Jinping warns of 'red line' as Hong Kong marks 20 years of Chinese rule
Strictly speaking, 'Hong Kong marks 20 years of Chinese rule' is not true.
When Hong Kong was handed over China, UK and China promised that capitalism and speech of freedom are to be preserved for 50 years(Until 2047).
So, Chinese rule should not have started at all. But, China seems to make Hong Kong an actual territory as early as possible by multiple political measures.