Justice department pushes to install national security judge in case as three pro-democracy legislators arrested over unruly scenes during debate

Hong Kong’s department of justice has asked that a national security judge take over the trial of an activist, even though he has not been charged with national security offences, in a move that underlines the erosion of the city’s independent legal system.

It came as a senior Chinese official called for “judicial reform” in Hong Kong and three pro-democracy legislators were arrested.

Hong Kong has plunged further into crisis, as a new law imposed by Beijing allowing the disqualification of 'unpatriotic' opposition members led to the immediate disqualification of four sitting legislators.

The move prompted the entire pro-democracy caucus to announce their resignation, and was heralded by the opposition politician Claudia Mo as 'the death knell of Hong Kong’s democracy fight'

• Hong Kong opposition lawmakers all quit after four members ousted

Disqualified legislator says move signals the end of ‘one country, two systems’

China has passed legislation allowing for the immediate disqualification of lawmakers in Hong Kong deemed dangerous to national security, in a move widely seen as heralding the end of political opposition in the city.

The measure, passed by China’s highest legislative body on Wednesday, bars anyone from Hong Kong’s legislative council who supports independence, refuses to recognise Beijing’s sovereignty over Hong Kong, seeks help from “foreign countries or foreign forces to interfere in the affairs of the region” or commits “other acts that endanger national security”.