'An outspoken critic of China's rulers, Professor Xu Zhangrun, has been released after six days in police custody, friends say.
The Beijing constitutional law professor was already under house arrest when he was detained on 6 July.
He had criticised China's response to coronavirus and what he sees as a Mao-like cult of personality under China's current leader, Xi Jinping.
The authorities have not confirmed his release from detention.
News of his release has come from friends speaking to international media outlets.
One friend told the Hong Kong-based South China Morning Post that Mr Xu, 57, returned home in the morning and was well.
It is not known why he was detained. After his arrest, a friend said Mr Xu's wife had received a call saying he was accused of soliciting prostitution while in the city of Chengdu - a charge the friend dismissed as ridiculous.
Open criticism of the authorities in China carries the risk of arrest and jail sentences. Mr Xu's criticism of the ruling Communist Party in a series of recent essays had drawn unfavourable attention from the Chinese government.'
- BBC,
Xu Zhangrun: Outspoken professor freed after six days, July 12, 2020
Context'..the perils that China is inviting by turning away from substantive economic and political reform..''Far too many American multinational corporations have kowtowed to the lure of China’s money and markets by muzzling not only criticism of the Chinese Communist Party, but even affirmative expressions of American values.' - Pence'..Sudan has outlined wide-reaching reforms..'