China has detained a prominent legal activist who had recently campaigned for greater government transparency.
A police order circulating Wednesday said Xu Zhiyong was detained a day earlier on suspicion of "gathering people to disturb order in a public place."
Authorities have not commented on the charge, which is often directed at government critics in China. But the detention was later confirmed by Teng Biao, a fellow lawyer and Xu's close friend.
Xu has been punished repeatedly by Beijing for his activism. In April, he was held under house arrest after calling for government officials to disclose their wealth. He had also recently campaigned for the release of other detained activists.
China recently has expanded its crackdown on those calling for more openness in government. Rights groups say the moves call into question Beijing's stated commitment of cracking down on rampant government corruption.
President Xi Jinping, who took over last year as the Communist Party's top leader, has vowed to make fighting graft a top priority of his government. He says failure to do so could jeopardize the party's hold on power.
But the continued arrest and prosecution of rights activists, such as Xu, suggest that the new leadership will be no more tolerant of criticism, even in areas where the government has acknowledged that reforms are needed.
Past punishment of Xu's activism has drawn international condemnation. In 2009, the government accused Xu of tax evasion and shut down his legal center, the Open Constitution Initiative, which he had used to push for legal reforms. The charges were later dropped.