Three Hong Kong activists who organised annual vigils commemorating Beijing’s 1989 crackdown on Tiananmen Square protests have been handed prison sentences of up to seven years.

Lee Cheuk-yan, 69, and Chow Hang-tung, 41, were convicted last month of inciting others to subvert state power, under the city’s controversial national security law. A third defendant, Albert Ho, 74, had pleaded guilty in January.

The office of United Nations human rights chief Volker Türk called for “these sentences to be quashed”.

Hong Kong and Macau were for years the only places on Chinese soil where people could hold gatherings to mark the Tiananmen crackdown – a highly sensitive and heavily censored topic in mainland China.

These gatherings were banned by Hong Kong’s authorities in 2020, citing Covid-19 policies, but never resumed. That same year, the national security law, which makes illegal a wider range of dissenting acts, officially came into force.

Authorities say the law is necessary to maintain stability, but critics argue it has eroded Hong Kong’s autonomy and created a climate of fear.

Lee, Chow and Ho were charged in 2021. They faced up to 10 years in prison after their conviction.

On Friday, the court sentenced Lee to seven years in prison, while Chow was handed seven years and three months. Ho, who pleaded guilty, was sentenced to five years in prison.

As the court session started, Chow and Lee stood up and smiled at the public gallery, which was full of people. Ho wore a serious expression.

After their sentences were handed down, Lee appeared to pray as he was led out of the dock, while Chow blew a kiss to those seated in the public gallery.

According to a court summary in August, Lee and Chow had “incited other persons to organise, plan, commit or participate in acts by unlawful means with a view to subverting the state power”.

Chow told the court in May the law itself was on trial.

A key part of the trial concerned the group’s slogan of “ending one-party dictatorship”, which the court said had incited people to undermine the Chinese Communist Party.

Lee’s wife, Elizabeth Tang, told Reuters that it was a “sad day” for her.

“I cannot imagine that he has to spend another three years in jail, it is really unacceptable,” she said, adding that Lee intended to appeal his sentence.

Chow’s mother Medina told a crowd outside the court not to be “overly saddened” about the verdict. “Do not lose heart. And above all, do not feel guilty,” she said, Reuters reported.

Speaking to the BBC before her arrest in 2022, Chow said she was “prepared to be arrested” and “willing to pay the price for fighting for democracy”.