A prominent Chinese human rights lawyer detained over a year ago in a sweeping crackdown has been released on bail, Hong Kong media said Monday, as it showed her praising her jailers.

Wang Yu was among one of more than 200 lawyers and legal activists held last July in a swoop on those who had taken on civil rights cases considered sensitive by China's ruling Communist Party, which tightly controls the court system.

She was bailed "in recent days," Phoenix TV said. Such releases are rare in China, and usually signal a suspect will continue to be closely monitored but will not face trial.

"I experienced the legal civilisation of China and humane care," Wang was shown saying on Phoenix, which has ties to China's government.

The exact circumstances in which the interview took place on Sunday were not clear.

AFP was unable to contact Wang for comment, nor authorities in Tianjin, where she had been held.

Chinese state-run media often show televised "confessions" from suspects in detention or on bail, in what lawyers say violates their right to a fair trial.

Phoenix TV is privately owned but was founded by a former general in China's army. Its reporters have said in interviews that the government closely oversees its content.

Working as a lawyer, Wang defended victims of sexual abuse as well as Ilham Tohti, an intellectual from the mostly-Muslim Uighur minority who was jailed for life in 2014 for separatism after he criticised government policies.

Wang's husband Bao Longjun, also a lawyer, remains under detention and cannot contact family members, she said in the interview.

She expected to meet her teenage son Bao Zhuoxuan, the broadcaster said.

Bao was held under a form of house arrest last year, family friends said, after he was seized by Chinese agents while trying to escape overland to neighbouring Myanmar.

China's President Xi Jinping has overseen a tightening of controls on civil society since assuming power in 2012, closing avenues for legal activism which emerged in recent years.

Like more than a dozen lawyers and legal activists, Wang was held in an undisclosed location for six months, before being transferred to a detention centre following her formal arrest in January.

The EU, the US and the United Nation's human rights representative have all called for the lawyers to be released.

China has not laid out detailed charges against them, but state media called the Fengrui firm where Wang worked a "criminal gang" which organised protests outside courthouses.

While under detention, Wang received an award from the American Bar Association, and the prestigious Ludovic Trarieux Prize for her work defending human rights.

But in the brief TV interview Wang said the awards were intended to "blacken the reputation of the Chinese government".

"I am Chinese. I only accept the leadership of the Chinese government," she added. "I do not accept these awards, and will not accept them in future".