Nine pro-democracy Hong Kong activists appeared in court on Thursday for their role in the 2014 Umbrella Movement mass protests. They’ve criticised the case as a form of political persecution.

The group of campaigners, including students and lawmakers, were charged the day after pro-Beijing leader Carrie Lam was selected as city leader by a committee skewed towards the mainland camp.

The case comes as fears grow that semi-autonomous Hong Kong's freedoms are increasingly under threat from Chinese authorities.

It also precedes an expected visit by China's President Xi Jinping in July to mark the 20th anniversary of the handover of Hong Kong to China by Britain in 1997.

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The nine activists, ranging from 22 to 73-years-old, were charged with either conspiring to cause public nuisance or inciting others to do so in relation to the 2014 protests, which called for fully free leadership elections.

The case was adjourned to May 25 after a brief hearing in magistrates' court, during which the defence requested a High Court jury trial so that the public could participate in the decision.

The defendants could face up to seven years in prison. They have yet to enter a plea.

Dozens of Beijing supporters and pro-democracy protestors faced off outside the court, yelling profanities at each other, before the nine defendants were due to emerge.

The group of activists were charged one day after pro-Beijing leader Carrie Lam was selected as city leader [Bobby Yip/Reuters]

Some pro-China supporters slapped a picture of activist Benny Tai Yiu-ting with a pink plastic slipper, mimicking a local custom practised by some residents where a shoe is used to beat an image of an enemy.

The 2014 uprising saw hundreds of thousands of people take to the streets to protest against Beijing's insistence that Hong Kong's leader - the chief executive - must be vetted by a 1,200-person committee before facing a public vote.

Speaking outside court, movement leader Benny Tai Yiu-ting told reporters the activists would not give up on the fight for democracy in Hong Kong.

"I believe our society is steeped with the spirit of civil disobedience," said Tai, co-founder of Occupy Central, one of the groups behind the 2014 Umbrella Movement rallies.

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"We won't give up until Hong Kong has real democracy and real universal suffrage," he added.

Rights group Amnesty International condemned the charges, saying the case showed Hong Kong's freedom of expression and right to peaceful assembly was "under a sustained attack".

New leader Lam has promised to try to unify divided Hong Kong, but opponents said the court case immediately undermined that pledge.

Source: News agencies