Rights lawyer Lu Siwei was extradited to China in September after being detained for over two months in Laos, his wife Zhang Chunxiao wrote on X, formerly known as Twitter.
"The judicial organs strictly handle cases according to the law and the relevant person's legitimate rights are fully protected," foreign ministry spokesperson Wang Wenbin told a daily briefing.
"The U.S. must not interfere through any means with Chinese judicial organs' handling of cases according to the law."
Lu was arrested in Laos on July 28 as he tried to travel to the United States to reunite with his wife and daughter, according to rights groups. He was detained by Lao police while boarding a train bound for Thailand, on charges of traveling on fraudulent documents.
He is currently being held in Xindu Detention Centre in Chengdu, Sichuan province, his wife wrote on X.
Two government-appointed defence lawyers were prevented by detention centre staff from delivering medicine to Lu earlier this week, said Bob Fu, founder of the U.S.-based NGO China Aid, who has been campaigning for Lu's release.
Calls to the detention centre were not answered. Zhang, his wife, declined an interview request from Reuters.
Lu had taken on politically-sensitive cases including one involving 12 Hong Kong citizens who were arrested by the Chinese coastguard in 2020 as they tried to flee on a boat to Taiwan.
His legal licence was revoked by Chinese authorities in 2021.
(Reporting by Laurie Chen and Andrew Hayley; Writing by Bernard Orr; Editing by Christian Schmollinger and Emelia Sithole-Matarise)
By Laurie Chen
