Twenty-eight years after People's Liberation Army (PLA) troops put an end to weeks of student-led pro-democracy protests on Tiananmen Square with tanks and machine guns, more than 20 dissidents remain in jail for campaigning over the massacre, rights activists said ahead of Sunday's anniversary.
Those who participated in the nationwide democracy movement have since been persecuted for their subsequent involvement in human rights activism or campaigns for constitutional government, including 2010 Nobel Peace Prize laureate and writer Liu Xiaobo, veteran journalist Gao Yu and rights activist Guo Feixiong, the overseas-based China Human Rights Defenders (CHRD) network said on Wednesday.
Activists Chen Wei, Chen Xi and Zhu Yufu are all also currently serving lengthy jail terms on subversion charges, while former student leader and Buddhist monk Wu Zeheng was jailed in 2015.
Lawyer Tang Jingling, Buddhist monk Sheng Guan and members of the banned opposition China Democracy Party (CDP) Chen Shuqing, Lü Gengsong and Hu Shigen are also current prisoners of conscience.
"Punishments for former 1989 participants are often harsher than for other prisoners, as authorities treat them as 'recidivists' with 'political motivation' to challenge the legitimacy of the one-party-ruled authoritarian state," the group said.
"Some had served prison terms for their role in the movement and resumed their democracy and human rights activities after being released," CHRD, which compiles reports from groups inside China, said in a statement on its website.
In total, CHRD said it had found 23 former 1989 activists currently behind bars in China, some of them, like Sichuan-based Chen Yunfei, for seeking to publicly commemorate those who died.
Crackdown on commemorations
In the central province of Hunan, police contacted more than 10 people in the provincial capital Changsha after they held an event commemorating the crackdown and posted a photo of themselves on social media.
"Everyone wanted to get together to to remember those unfortunate students who were killed, and to discuss the event," participant Feng Jun told RFA. "Then we took a photograph to mark the anniversary."
Fellow participant Zhu Chengzhi said he had received a phone call from police in his home city of Shaoyang on Wednesday afternoon.
"They saw the photo online, and they wanted to ask me about it, whether it took place in Changsha," Zhu said, adding that he expects to be under surveillance from Thursday or Friday ahead of the June 4 anniversary.
In the eastern province of Shandong, retired university professor Sun Wenguang said 13 activists from the province had traveled out of town to hold their memorial, 10 days ahead of the anniversary.
"There are around 10 people down there ... and they wouldn't let me leave the main door of my apartment building," he said. "Eventually they let me leave, but then they restricted my movements."
In the troubled northwestern region of Xinjiang, security services are on high alert as the anniversary coincides this year with the Muslim holy month of Ramadan.
"The authorities are terribly nervous right now, especially around areas where [ethnic minority Muslim] Uyghurs are concentrated," Dilxat Raxit, spokesman for the exile World Uyghur Congress group said.
"They are now carrying out door-to-door searches by night of entire apartment blocks," he said. "They are forcing people to stay up late to see whose lights are still on. If anyone's lights are still on, they have to report them."
"There is now a set of extreme reporting measures being implemented, particularly in [regional capital] Urumqi during Ramadan," Raxit said.
'Never forget. Never give up'
And in the southwestern province of Sichuan, relatives of two people detained last year for selling bottles of spirits bearing labels commemorating June 4, 1989 issued a statement calling for their immediate release.
Teahouse proprietor Fu Hailu and poet Ma Qing were taken away by police in the provincial capital Chengdu after they brought out the alcohol, which bore the words "June 4, 1989" and a cartoon of a man in front of an advancing column of tanks on the label. The label also read: "Never forget, never give up."
"Was that era of history all for nothing?" the statement said. "Please can the government give us some clarity about what can have happened that was so bad they won't even allow future generations to remember it."
"Where in Chinese law does it say that you can't remember history? Please release them immediately!"
Fu's wife Liu Tianyan said she had hardly believed at first that her husband's detention was linked to the bottles' labels.
"I had heard about June 4, but I didn't really know much about it, so I read a lot about it after that, and I think that it was a terrible catastrophe, regardless of the exact circumstances," she said.
"In my mind, it's similar to the 2008 Sichuan earthquake; a terribly painful event and worthy of reflection. It's normal to want to mourn the departed."
Reported by Yang Fan and Qiao Long for RFA's Mandarin Service, and by Hai Nan for the Cantonese Service. Translated and edited by Luisetta Mudie.