A common practice, it involves security agents taking prominent dissidents away from cities during sensitive events to keep them quiet.

However, the crackdown did not stop Chinese dissidents from attending the vigil in Hong Kong, with representatives of the Independent Chinese PEN Centre, which helped secure Liu Xia’s release, travelling to the city.

There were also several Mandarin-speaking teenagers in the crowd, but they would not say if they had travelled from the mainland to commemorate Liu Xiaobo.

Welcome release of Liu Xia comes at a time when China needs friends

“I just fear Beijing’s control will tighten in the future,” he said. “But Liu Xia’s release told Hongkongers that we need to hold on and strive for what’s right, attend rallies or vigils whenever we can.”

In Berlin, the president of the PEN Centre, Liao Tianqi, said Liu Xia would not attend a vigil there in her husband’s honour, deliberately keeping a low profile while her brother remained in China.

“If she attends, something she doesn’t want would happen,” Liao said. “It’s not because she’s physically weak, just she could not attend.”

The president added that Liu Xia expressed a note of thanks to Hongkongers and for marking the anniversary of her husband’s death.

On the mainland, Hu Jia, a Beijing-based dissident who knew Liu Xiaobo, said he was going to be taken to Chongli, four hours outside Beijing.

“They said I could not go near the sea,” he said.

Three other friends or supporters of Liu, who declined to be named, said they had been contacted by the authorities and told not to host memorial events or protests to mark the date.

The pro-democracy icon, 61, died of liver cancer on July 13 last year while in custody in a hospital in Shenyang, in mainland China’s northern Liaoning province.

He had been serving an 11-year jail sentence since 2009 for “inciting subversion of state power” after he helped write a petition known as Charter 08 calling for sweeping political reforms in China.

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The alliance, which estimated about 500 people attended the vigil, vowed to continue to care for Liu Xia’s brother, Liu Hui, and other dissidents. Police put the number of people at the vigil at 350.

Albert Ho Chun-yan, the alliance chairman, said the choice of the waterfront location was fitting a place to remember the late dissident, who was cremated and had his ashes scattered at sea.

“The vast sea can contain his great dream, vision and love,” Ho said.

The chairman also said that while Liu had died, the authorities could not wipe out his spirit.

A man who only wished to be known as Matt said it was important to remember the pro-democracy icon’s sacrifices.

He said he hoped for a free society for China in the future.

A woman at the vigil, who only gave her name as Clara, said she was happy Liu Xia had been able to leave China.

“I feel happy for her but at the same time, I feel it is sorrowful for her to be used as a chip in [China’s trade war with the US].”

Like Matt, Clara hoped one day there would be a China that respected human rights, and those who fought for democracy.

Sister of late Chinese dissident Li Wangyang thanks Hongkongers for support of democracy push and 1989 Tiananmen victims

Liu Xiaobo first spent time behind bars in the wake of the Tiananmen crackdown, during which time he negotiated with the student leaders and the military commander to allow students to leave the square in peace on the morning of June 4, as People’s Liberation Army soldiers and tanks moved in.

His wife, a 57-year-old poet and artist, who has never been charged with any crime but was placed under house arrest in 2010, is being treated for serious depression in Germany.

Additional reporting by Reuters