Authorities in Beijing have warned civil rights campaigner Hu Jia not to give any more interviews to foreign media organizations and to stay away from further activism.
But the activist has questioned the legality of the government order.
Hu, who rose to prominence in the civil rights community for his advocacy on behalf of AIDS patients, was released from a three-year jail term for subversion in June, but has been subjected to continual police harassment, a Hong Kong-based rights group said.
Hu has been warned not to give interviews to foreign media organizations and to give up his rights campaigning activities, the China Rights Defenders website said.
Hu told RFA's Cantonese service that there was no legal basis for the order, however.
"We are all free citizens with freedom of movement, and there is no legal basis whatsoever to prevent us from meeting up with each other," he said.
He said the state security police had paid him several visits since his release from prison, threatening to detain him again if he stepped out of line.
"I think the most recent time was my last warning," Hu said. "They told me that even if I could cope with [the pressure], my mother wouldn't be able to."
"This is tantamount to taking my family hostage, and it made me extremely angry," he said.
Political rights deprived
Hu said he would be turning down further media interviews, as he still had to serve two years' deprivation of political rights in addition to his jail term.
Teng Biao, a lecturer at the University of Politics and Law in Beijing, said police threats are unlikely to silence China's rights activists.
"The ones who dare to speak out will continue to speak out," Teng said. "Those who dare not will remain silent."
"The police are afraid of everything, the Arab spring, everything, including rights campaigners," he said.
Black bag over head
Meanwhile, Hu's wife Zeng Jinyan reported via her microblog account on Monday that Teng's colleague Xiao Han had been taken away by Beijing police with a black bag over his head at the weekend.
"There must be a reason for this escalation in their treatment [of him]," Zeng wrote.
Beijing-based rights lawyer Pu Zhiqiang said he had expected such behavior in the wake of the Arab uprisings earlier this year, but that Xiao's detention seemed unusually harsh.
"Xiao has very strong views but they are mostly expressed in his books and lectures and articles," Pu said. "He is just giving his opinion."
"For them to treat a lecturer in this way is a sign they are taking a much harder line," he said.
Reported by Grace Kei Lai-see for RFA's Cantonese service, and by Gao Shan for the Mandarin service. Translated and written in English by Luisetta Mudie.