Authorities in the southwestern Chinese province of Sichuan have formally detained a prominent rights activist on subversion charges after he visited the grave of a victim of the 1989 military crackdown on student-led pro-democracy protests, his lawyer said. Chen Yunfei, 47, a former 1989 Tiananmen activist who has campaigned vigorously for human rights protections and against environmental pollution in the past two decades, was initially detained on March 25 near Sichuan's provincial capital, Chengdu. He has been charged with "incitement to subvert state power" and "picking quarrels and stirring up trouble," his lawyer Ran Tong told RFA, who said the charges are contradictory, if applied to a single individual. "This just shows that they just detained him in a big hurry, and now they can't find excuses," Ran said. "The charge of picking quarrels and stirring up trouble implies that you are deliberately disturbing public order, but not that you have an aim." "Incitement to subvert state power has a clear motive implied; that you are trying to overthrow the political system," he said. Ran, who recently visited Chen in a police-run detention center, said the charges are a form of official retaliation for Chen's years of activism. "How can a regular person overthrow state power? Only someone as high-ranking as[former security czar] Zhou Yongkang would be able to do that," Ran said. "President Xi... told us that we should have curbs on official power, and Chen Yunfei was responding to his call," he said. "We are talking about a single individual trying to instigate some sort of monitoring of officialdom, and someone in officialdom taking offense at this," Ran said. "Why do they pin such big charges on him? Are citizens forbidden to speak out? This is incomprehensible," he said. Political persecution Fellow activist Luo Kaiwen, who was with Chen when he was detained, said the detention amounts to political persecution by the ruling Chinese Communist Party. "This is political persecution[of Chen] by the Communist Party," Luo said. "This is a stitch-up." He said Chen was detained after visiting the grave of Tiananmen massacre victim Wu Guofeng along with a group of fellow activists. "How is paying respects to the martyrs of June 4, 1989 subversion?" Luo said. "What quarrels did he pick, or trouble did he stir up?" "The whole world should speak out on behalf of Chen Yunfei," he said. Sichuan-based petitioner Wang Rongwen said the charges seemed "very heavy" compared with Chen's actions. "It's clear that they plan to charge him with a serious crime, otherwise they wouldn't do this," Wang said. "I am definitely worried about him." "Long line of subversives' Beijing-based rights activist Hu Jia wrote via Twitter: "Chen Yunfei is the latest in a long line of subversives from Sichuan. This case is similar to that of[detained rights lawyer] Pu Zhiqiang, in that they have brought criminal charges and political charges against the same person." Chen last spoke to RFA after he and a group of fellow activists were "forcibly dragged" to the local police station after they gathered outside a petrochemical plant in Sichuan's Pengzhou county to protest alleged pollution on March 6. Last year, the authorities launched a nationwide crackdown on activists and family members of victims of the 1989 military crackdown on the Tiananmen Square student-led pro-democracy movement in the run-up to the 25th anniversary on June 4. Some, including lawyer Pu Zhiqiang, remain behind bars, charged with "incitement to subvert state power." The government bans public memorials marking the event, and has continued to ignore growing calls in China and from overseas for a reappraisal of the 1989 student protests, which it once styled a "counterrevolutionary rebellion." The number of people killed when People's Liberation Army tanks and troops entered Beijing on the night of June 3-4, 1989, has never been confirmed.