US Republican Party presidential hopeful Marco Rubio has accused China of using “tired tactics of repression and intimidation” to “tighten its grip” on Hong Kong.

In a move likely to anger

Beijing and the Hong Kong government, Rubio and fellow US congressman Chris Smith, who co-chairs the Congressional-Executive Commission on China, also called into question the criminal prosecution of student leaders at the forefront of the 2014 Occupy protests .

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A statement issued by the two congressmen described the trial of high-profile student activist Joshua Wong Chi-fung as “very disturbing”, adding that it appeared to be “nothing more than political muscle flexing targeting those who dared to stand up for freedom and democracy.”

So far, neither the central government nor the Hong Kong administration have responded to the statement.

It follows a letter sent by Rubio to Chief Executive Leung Chun-ying six months ago when Wong was first charged along with other student leaders, questioning their prosecution over alleged

contempt of court for contravening a legal injunction imposed on their activities in Mong Kok during Occupy protests in late 2014.

“Instead of putting Joshua Wong on trial, the Hong Kong government should be promoting and consulting him and his fellow student activists as the best hope for Hong Kong’s future,” said Smith.

Rubio’s letter to the Hong Kong leader, meanwhile, also “noted with concern” the travel restrictions placed on many students who participated in the 2014 protests which have limited their ability to go to the mainland.

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The presidential hopeful, who is running a poor second to Donald Trump for the Republican party nomination ,said the trajectory of recent events in Hong Kong was troubling and merited greater attention from the Obama administration.

Rubio pinpointed the recent disappearance of five booksellers from Causeway Bay Books – which specialises in books banned on the mainland – and “shrinking academic and media freedom”, saying they called into question Beijing’s commitment to the principle of “one country, two systems”.

“It is against this backdrop that Joshua’s case goes to trial,” Rubio added. “We will be watching closely how it is handled. He and his fellow students represent the future of Hong Kong, not Beijing’s tired tactics of repression and intimidation.”

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