HONG KONG — Activist Joshua Wong was released on bail Tuesday pending appeal against a jail term over pro-democracy protests.

Wong was jailed for three months last week, the second time he has received a prison sentence for his involvement in the Umbrella Movement.

Campaigners fear political debate in the semi-autonomous city is being shut down with a raft of court cases against activists involved in the mass 2014 protests.

Wong, 21, who became the face of the rallies, was jailed Wednesday on a contempt charge for obstructing clearance of a major protest encampment, to which he had pleaded guilty.

Wong was released on bail as a judge acknowledged he had grounds to appeal the sentence.

He is already on bail pending an appeal over a six-month sentence for another protest-related offense.

Court of Appeal judge Andrew Cheung said the original sentencing had "not given any or any sufficient consideration" to Wong's age at the time of the offense, when he was a teenager.

Fellow activist Raphael Wong, who was jailed for four months and 15 days over the same incident, was denied bail as the judge ruled there were no grounds for appeal on the existing legal points.

Dozens of protesters gathered outside court Tuesday chanting "Political persecution! Abusing the courts! Civil disobedience! No fear!" ahead of the hearing.

The Umbrella Movement was an unprecedented rebuke to Beijing as tens of thousands of protesters brought parts of the city to a standstill.

They demanded fully free leadership elections to replace a system where Hong Kong's chief executive is selected by a pro-Beijing committee.

The rallies failed to win concessions and since then leading activists have been charged over their involvement.

Beijing has been further incensed by activists calling for independence for Hong Kong since the Umbrella Movement failed to win reform.

Wong's party Demosisto wants self-determination for the city.

Hong Kong has been governed under a "one country, two systems" deal since 1997, when Britain handed the territory back to China.

The agreement allows citizens rights unseen on the mainland, including freedom of speech, a partially directly-elected parliament, as well as an independent judiciary, but there are concerns those liberties are being eroded.

Wong was jailed for six months in August on unlawful assembly charges for involvement in the storming of a fenced-off government forecourt known as Civic Square in September 2014, which sparked the wider Umbrella Movement rallies.

He served over two months behind bars before being granted bail pending an appeal. — AFP