In the run-up to a five-yearly congress of the ruling Chinese Communist Party, authorities have stepped up detention and surveillance of activists reporting on human rights violations by its officials.
Editor Ding Lingjie of the Civil Rights and People's Livelihood Watch website is currently missing, believed detained, in Shandong's Zibo city, where she was on vacation, fellow activists reported on Thursday.
Ding was reported missing by the landlord of a place she had rented, and her daughter has filed a missing person's report with police, Xu Qin, head of the China Rights Observer and sister-group Rose China, told RFA.
"I can't get in touch with her, so of course I'm very worried," Xu said. "We haven't had any kind of notification from the police station, either, although it's been more than 24 hours now."
Fellow editor Shi Yulin was placed under surveillance several days ago, a source told RFA.
"She's somewhere out of town right now, near Xianqiao," the source said. "The state security police here told me."
"According to the state security police [in her hometown of] Yichang, she's not allowed to see anyone, nor is she to give interviews to the foreign media. Those are the requirements."
Website founder Liu Feiyue is currently being held incommunicado on suspicion of "incitement to subvert state power" in the Suizhou No. 1 Detention Center.
Meanwhile, Wu Lijuan, editor at the Rose China human rights organization, is also under round-the-clock surveillance by state security police outside her home in Qianjiang city in the central province of Hubei, Xu told RFA.
"Wu Lijuan, who works for us here at Rose China, hasn't been detained, but she's under 24-hour surveillance," Xu said. "I'm OK, but I am also under round-the-clock surveillance, via the internet."
Xi's widespread crackdown
Calls to Wu Lijuan's cell phone rang unanswered on Thursday.
Rose China is linked to the China Rights Observer newsletter set up by veteran democracy activist Qin Yongmin in the provincial capital Wuhan.
Qin is currently awaiting trial on charges of "incitement to subvert state power" at the Wuhan No. 2 Detention Center, while his wife Zhao Suli has been missing for more than two years.
Xu said censors have also targeted the group's website, deleting a number of articles, including one written by Qin.
Authorities in China have stepped up nationwide "stability maintenance" measures targeting anyone with a critical opinion of the government, as President Xi Jinping looks set to reshuffle his leadership team and consolidate his personal grip on power at the 19th Party Congress on Oct. 18.
Human rights campaigner Zhai Yanmin was reported missing, believed detained, earlier this week, his relatives told RFA on Tuesday.
"I think he disappeared after he put me on the train [on Monday]," Zhai's wife Liu Ermin told RFA. "His phone has been switched off the whole time."
"I told him I caught the train, and he said I should take care of myself," she said. "I said OK, and he hung up. About an hour later, the neighborhood committee called his cell phone and it was switched off, so they wanted me to try him, but it was switched off when I called it, too."
"It is still switched off," Liu said.
Xi has already shown himself to be far less willing to tolerate dissent and criticism than his recent predecessors, rolling out a massive ideological crackdown at the start of the year that includes detailed policing of foreign online content, social media activity and the country's news organizations.
An Aug. 25 directive issued by a "stability maintenance" steering group under the party's Central Committee orders complaints departments at all levels of government and party to ensure that no petitioners are allowed to crowd around the outside of the government buildings in the run-up to the party congress.
Reported by Hai Nan for RFA's Cantonese Service, and by Yang Fan for the Mandarin Service. Translated and edited by Luisetta Mudie.