(Yicai Global) Nov. 9 -- JA Solar Technology's shares plunged by the exchange-imposed limit today on the news that the chairman of the world’s fourth largest solar panel supplier has been taken into custody and is under investigation.

The Beijing-based firm’s stock [SHE:002459] plummeted 10 percent to close at CNY32.83 (USD5).

Jin Baofang, who is also actual controller and general manager of the company, has been arrested, JA Solar said yesterday, citing the supervisory commission of Pingdu city, northeastern Shandong province.

No reasons were given for the probe, but earlier today JA Solar said that an internal investigation had not uncovered any instances of financial fraud, embezzlement by major shareholders or other acts that could harm the interest of shareholders. Its words, however, did little to placate investors.

68-year-old Jin holds 57 percent equity in JA Solar. His family ranked 113rd on the Forbes China Rich List this year with wealth of CNY29.3 billion (USD4.4 billion).

The company has been doing very well. Net profit almost doubled in the third quarter from the same period last year to CNY590 million (USD89.5 million), according to the firm’s latest earnings results. Operating revenue jumped 25 percent to CNY5.8 billion (USD879 million).

Since returning to the mainland stock market last year after delisting from the Nasdaq in 2017, JA Solar has announced a CNY10.4 billion (USD1.6 billion) spending plan, its biggest ever, on new manufacturing bases to expand its output of silicon wafers, batteries and components.

The firm’s new 10-gigawatt factory in Yiwu, eastern Zhejiang province opened last month, producing mostly large 182-millimeter x 182 mm wafers.

Editors: Liao Shumin, Kim Taylor