Evergrande Chairman Hui kept in special detention center in Shenzhen

Hui Ka Yan, the chairman of China Evergrande Group — the company at the center of the country's property sector crisis — has been moved to a special detention center in Shenzhen, two sources with knowledge of the matter said.

Hui, 65, has not been seen in public since he was taken away by Chinese authorities a year ago and his current whereabouts have not been previously reported.

After China's securities regulator found Evergrande's flagship unit had inflated earnings and committed securities fraud, Hui was fined $6.6 million in March and barred from the securities market for life. Evergrande was ordered into liquidation in January.

Hui, who was once China's richest man, is not known to have been formally charged with any crimes and it is unclear how long he will remain in detention or whether he will be tried or set free.

Chinese authorities have detained many former high-flying business executives and some have remained in detention for years with little or no information about their fate.

The property tycoon was initially under house surveillance in Beijing after his arrest, according to one of the sources.

He was transferred to Shenzhen a few months ago to allow him to more easily communicate with top Evergrande executives, said the second source. Evergrande is headquartered in the neighboring southern city of Guangzhou and its wealth management unit is based in Shenzhen.

The sources declined to be identified due to the sensitivity of the matter.

China's Ministry of Public Security and the Shenzhen municipal government did not respond to Reuters requests for comment, nor did Hengda Real Estate, Evergrande's main unit. Evergrande's liquidators, who have been appointed by a Hong Kong court, declined to comment.

Hui founded Eve