The youthful figurehead of Hong Kong’s democracy movement, Joshua Wong, was jailed Thursday for his role in the 2014 protests known as the Umbrella Revolution.

Wong, 20, was sentenced to 8 months for illegal assembly alongside his party colleague, the ousted legislator Nathan Law, 23, who received 10 months for participating in, and inciting, illegal assembly. Also jailed on similar charges was student leader Alex Chow, 26, who was given 8 months. Taking into account the community service they have already performed, the three will spend 6, 8, and 7 months in prison respectively.

Under Hong Kong law, the sentences — which come after frustrated prosecutors twice appealed earlier, non-custodial punishments — bar the three from standing as candidates in elections for five years.

The development deals a blow to Wong and Law’s fledgling party, Demosisto, and scuppers Wong’s hopes of running for the legislature after he attains the age of majority in October. It also sends a warning to those agitating for greater freedom in the semi-autonomous enclave, which has struggled to fend off Beijing’s gradual political encroachment since it came under Chinese sovereignty 20 years ago.

A defiant Wong tweeted a message from the court after the sentence was read out, vowing to continue the struggle for greater political freedom.

In the court, enraged supporters chanted “Shame of the Department of Justice” and “Release the three of them.”

After the sentences were read, Demosisto issued a statement condeming the hearing as a de facto “retrial” and said that the tougher punishments show that the government was “determined to put peaceful protestors behind bars” and to silence dissent “by abusing judicial procedures.”

Wong, Law, and Chow are being jailed for over their decision to storm the forecourt of Hong Kong’s government headquarters, together with around 100 other demonstrators, on Sept. 26, 2014.

That action was the opening gambit in 79-days of massive protests and peaceful street occupations, which brought central areas of Hong Kong to a standstill. Protesters called for the implementation of full democracy in Hong Kong and for the territory’s right to self-determination — demands that alarmed both local authorities and officials in Beijing.

The three activists were taken to prison after the sentences were imposed by a panel of judges at the Court of Appeal made up of vice-president Wally Yeung, and justices of appeal Derek Pang and Jeremy Poon. A last-minute letter submitted by Wong’s legal team, the contents of which were not publicly disclosed, was criticized by the Yeung as “inappropriate” and “disruptive to the court.”

Before the hearing, supporters and press crammed the entrance of the court in unprecedented scenes. Supporters chanted “We are all Joshua Wong! We are all Nathan Law! We are all Alex Chow!” before the three made impassioned speeches asking Hongkongers not to lose hope and to continue the fight for greater political freedom. Law said: “No matter today’s outcome, we are free in our hearts.”

Chow told the crowd “When we are on the side of truth and justice, we can move more people with our sacrifice,” then hugged his friends. Wong said that it had been an “honor” to be part of the 2014 protests, and just before entering the courthouse sent out a tweet that read “Student movement, fearless.”

Wong and Law were originally given community service orders, and Chow a three-week suspended jail sentence, last year. Hong Kong’s political establishment was incensed at what it called the leniency of those punishments, and prominent figures have made no secret of their desire to see the trio jailed. In an open letter to the Secretary for Justice, pro-Beijing legislator and former Hong Kong Law Society president Junius Ho described the original penalties as “grossly inadequate.” Deputy director of public prosecutions David Leung said they were “rather dangerous.”

In an exclusive interview conducted with TIME Wednesday, Wong said “Judicial independence is under threat because of the Department of Justice’s loyalty to China. I hope people will realize that. One decade ago, people described Hong Kong as a place without democracy but with rule of law. Now Hong Kong has already transformed into an authoritarian regime.”

In a statement to the media, the Department of Justice said that there was “absolutely no basis to imply any political motive on the part of the Department of Justice in this case,” and maintained that the three were being jailed for their “disorderly and intimidating behavior.”

However, Willy Lam, adjunct professor at the Centre for China Studies of the Chinese University of Hong Kong, told TIME that “Reassessing completed sentences creates a dangerous precedent for Hong Kong due to the public perception that the judiciary could be buckling under pressure not only from the [local] administration but also from Beijing.”

He added: “There are widespread suspicions among pro-democracy politicians, NGO activists, lawyers and liberal intellectuals that the last line of defense for [Hong Kong’s] high degree of autonomy – judicial independence – is in the process of being breached.”

Meanwhile, the U.S. Congressional Executive Commission on China issued a statement condemning the sentences. “These sentences are another severe blow to Hong Kong’s reputation as a city governed by the rule of law,” said co-chair Representative Chris Smith. “Beijing is actively trying to decimate the pro-democracy movement using Hong Kong’s courts and prosecutors to further its political agenda.”

In a media statement, Amnesty International called the punishments “an attack on freedom of expression and peaceful assembly.”

Amnesty’s local director Mabel Au said: “The relentless and vindictive pursuit of student leaders using vague charges smacks of political payback by the authorities.”

Wong’s incarceration will form the first hiatus in a meteoric political career that has seen him rise from high school activist and protest leader to becoming the founder of his own political party and an inspiration not only to Hong Kong’s democracy movement but to youthful campaigners elsewhere in Asia. Earlier this year, he became the subject of the Netflix documentary Joshua: Teenager vs. Superpower. In 2014, the then 18-year-old Wong was featured on a cover of TIME magazine’s international edition and named by TIME as one of the world’s most influential teenagers.

—With reporting by Feliz Solomon/Hong Kong and Kevin Lui



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