Hong Kong authorities on Wednesday (January 6) arrested more than 50 protest leaders for allegedly violating the city's security law.

Amnesty International’s Asia-Pacific Regional Director Yamini Mishra said: “This shocking crackdown on Hong Kong’s political opposition – sweeping up candidates, activists and pollsters alike – is the starkest demonstration yet of how the national security law has been weaponised to punish anyone who dares to challenge the establishment."

Footage filmed on November 23 shows high-profile Hong Kong activist Joshua Wong and fellow activists Ivan Lam and Agnes Chow after they were remanded in custody after they pleaded guilty to unlawful assembly.

Additional footage filmed December 2 shows a police van carrying the three activists after they were handed jail sentences.

Pro-democracy activists Joshua Wong, Agnes Chow and Ivan Lam were jailed by West Kowloon Magistracy on Wednesday for their roles in an anti-government protest that saw police officers trapped inside their headquarters in Wan Chai for hours.

Wong received 13.5 months behind bars, Chow 10 months and Lam 7 months, with their jail terms reduced in light of their guilty pleas.

But the magistrate said she had used a higher starting point for sentencing Wong because he had taken a "leadership role" in the protest.

Pro-democracy activists Joshua Wong, Agnes Chow and Ivan Lam were remanded in custody on Monday after pleading guilty to charges related to a major protest outside police headquarters last year.

The trio sentenced on December 2.