This came after the prosecution sought an arrest warrant against Ra on Friday. Ra has been under custody for interrogation since Tuesday.
The company said in a disclosure Wednesday it has nominated an acting CEO, adding that no allegations had been proven.
|Nature Cell CEO Ra Jeong-chan (Nature Cell)|
Prosecutors raided the company office in June after the Financial Services Commission handed over case to the prosecution.
Nature Cell shares hit the price floor to 10,650 won ($9.40) per a share since around 10 a.m., falling 30 percent in closing compared to Tuesday. The share price has been on a rollercoaster ride since November last year. Standing at 6,920 won on Oct. 31, 2017, Nature Cell share price peaked at 64,600 won in March 16 and has since drifted down.
By Son Ji-hyoung