The three Umbrella Movement leaders jailed Thursday in Hong Kong were at the forefront of the 2014 pro-democracy rallies which brought parts of Hong Kong to a standstill for months in an unprecedented rebuke to Beijing.

Joshua Wong, Nathan Law and Alex Chow were sentenced to six to eight months in prison for their role in a protest that sparked the mass demonstrations.

Rights groups and supporters called the case against them "political persecution" and their imprisonment comes as a fresh blow to forces pushing for political reform in the semi-autonomous city.

Here we look at the three activists' stories.

Face of the movement: Joshua Wong

Scrawny, with gaunt features and a studious frown, the bespectacled 20-year-old activist is now one of Hong Kong's highest profile prisoners.

Wong was the unlikely hero who led a movement inspiring hundreds of thousands to call for fully free elections for Hong Kong in 2014.

Then just 17, he spearheaded the mass Umbrella Movement protests, which were a reaction to restrictions from Beijing on how Hong Kong's next leader would be chosen.

Wong captured the attention of the world as David against the Goliath of the Chinese Communist Party, and was hailed as one of the world's most influential figures by Time, Fortune and Foreign Policy magazines. He even became the subject of Netflix documentary "Teenager vs Superpower", released this year.

A student at the Open University of Hong Kong, Wong told AFP he was mentally prepared for a jail sentence and would continue to study behind bars, but felt "guilty and sorry" about what he had put his loved ones through.

Born to middle-class Christian parents Grace and Roger Wong, he began his life of activism aged 13 with a protest against plans for a high-speed rail link between Hong Kong and the mainland.

At the age of just 14, Wong campaigned successfully for Hong Kong to drop a pro-China "National Education" program, rallying a crowd of 120,000 to his cause.

Since the end of the Umbrella Movement, he has been denied entry into Malaysia and Thailand, attacked in the street, and abused by pro-China protesters in Taiwan. But he has said he will fight on.

In one of his last public speeches before his jailing, Wong declared: "I hope that nobody gives up hope on Hong Kong, we can still win."

Disqualified lawmaker: Nathan Law

Softly spoken 24-year-old Nathan Law often stood beside Wong as they addressed protest crowds camped out in Hong Kong during the Umbrella Movement.

The two went on to found pro-democracy party Demosisto, which campaigns for Hong Kong people to have the right to self-determination over their future sovereignty.

Law became the youngest lawmaker ever elected to Hong Kong's legislature last September after winning 50,000 public votes.

But in July, he was disqualified by Hong Kong's High Court for changing his oath of office during his swearing in to reflect his frustrations with Chinese authorities.

Law quoted Gandhi before taking his pledge, saying: "You will never imprison my mind", and used intonation to make his oath sound like a question.

He was barred after Beijing intervened to insist pledges were take in a "solemn and sincere" manner.

Born in mainland China to a working class family, Law moved to Hong Kong at the age of six where he thought of becoming a journalist or an actor.

But a lightbulb moment at a school assembly critical of the late Chinese Nobel laureate Liu Xiaobo agitated him and set his course.

At university he became involved in student politics before he was catapulted into the spotlight in 2014.

Law captures the quieter moments of his life with pictures and videos of his cats on Instagram.

Back in the spotlight: Alex Chow

Along with Wong and Law, Chow, now 26, was also at the forefront of the mass protests in 2014, as one of the main organisers of the movement.

He was adamant that student protesters should not compromise on their demands for fully free elections.

Ultimately their calls for change fell on deaf ears as Hong Kong and Beijing authorities gave no concessions.

Chow spoke of the high pressure he was under from his parents, who he described as pro-establishment moderates, during the months-long movement and afterwards stepped out of the limelight to concentrate on his studies.

A day ahead of his jailing he told AFP he was not scared.

"When we are willing to sacrifice what we have, there is nothing to fear," he said.

Chow added that he had deferred his masters dissertation at the London School of Economics and planned to defer his enrolment into a doctorate programme in geography at the prestigious Berkeley university in California as he prepared for prison.

Source: AFP