Is democracy under threat in Hong Kong?

It is 20 years since Hong Kong was returned to China after more than a century of British rule.

Two decades on, what is the state of democracy in the country? And is the so-called "one country, two systems" principle working?

For BBC Newsnight, Danny Vincent reports.

The UK government says it takes its commitments to Hong Kong "very seriously". A Foreign Office spokesperson said: "We hope and expect that 'one country, two systems' will be respected and successful long into the future."