This tension reached a boiling point when in September the head of Hong Kong proposed a bill that would extradite Hong Kong's criminals into China, a country whose judicial system can be labeled as a farce at best. In China, the government decides if you are guilty or not and that means the government can use the Judicial system as a means of political control and elimination.
Of the 7 million people that live in Hong Kong, this democratic freedom is at the backbone of a territory that wants nothing to do with China but realistically has no other option. China is too powerful and Hong Kong's physical location on the Southern border of China affords it no geographical protection. 76 percent of Hongkongers do not consider themselves Chinese but 100% of them have no choice.
Millions of Hong Kong's citizens came out in protest, a liberty that Chinese citizens do not enjoy. The bill would eventually be withdrawn but by that point the damage had already been done. In Hong Kong, major corporations that have favored the Chinese government are routinely vandalized. The Chinese government treats these protests as a form of direct dissent and anyone who expresses support for Hong Kong's protesters is deemed to be anti-China.