The brother of imprisoned rights lawyer Gao Zhisheng is petitioning China's Justice Ministry for information on his condition and the right to visit him.
Gao Zhiyi made the announcement Monday on his fourth trip to Beijing in search of news.
There had been no information at all about Gao Zhisheng for more than a year and a half until state media said in December that he was being sent to prison for three years for violating his probation.
He is believed held in remote Shaya county in the northwestern region of Xinjiang.
Gao advocated for constitutional reform and property rights and defended political and religious dissenters.
He was convicted in 2006 of subversion and sentenced to three years but released on probation.