The Supreme People's Court said on Wednesday that the case involving the country's former security chief, Zhou Yongkang, has not yet entered legal proceedings.

The court's spokesman, Sun Jungong, said information on the case has not yet been passed to the top court, adding that the investigation is still ongoing.

The central government announced on July 29 that it had launched a corruption investigation into Zhou, a former member of the Standing Committee of the Political Bureau of the Communist Party of China Central Committee, saying he is being probed for "serious disciplinary violations".

Zhou, 71, is the highest-profile figure caught up in President Xi Jinping's sweeping crackdown on corruption and is the most senior official to be put under investigation since China's reform and opening-up began in 1978.

On Tuesday, the top court's president, Zhou Qiang, said the Party's decision to investigate Zhou demonstrates that no Party member is above the law.

"All Party members, no matter what administrative levels they are at or how long they have been in the Party, must operate within the margins of discipline and law, and they should receive supervision," he said.

He also said the investigation of Zhou's case fully reflects that in China no power exists out of the cage of the country's institutions, referring to a well-known anti-graft guideline put forward by President Xi.

The situation in the judiciary is not always beyond reproach, and there, too, work is being done to stamp out corruption, he added.

"We must ensure our court system is clean, and avoid judicial corruption," he said.

Since August, several judges in Liaoning province have been under investigation on suspicion of dereliction of duty and taking bribes, provincial prosecutors said.

Ten judges from the court in Fushun, in the province's Qingyuan Manchu autonomous county, were questioned in May and July, and prosecutors said most are suspected of accepting bribes, perverting the law, abusing their power and rendering illegal verdicts.

Li Wei, president of Dalian Intermediate People's Court in the province, is also being probed for alleged serious disciplinary violations.

In March, when the two sessions were held in Beijing, the top court vowed to deal severely with judicial employees who break the law.

Last year, 381 judicial workers, including judges and prosecutors, were investigated on suspicion of violating laws and discipline. Of those, 101 received criminal punishments, according to the top court's work report.

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