The new sum was a 10-fold increase from the 50 million won (Sh4.3mn) originally offered last Thursday for Yoo Byung-Eun, patriarch of the family that owns Chonghaejin Marine Co.
Chonghaejin was the owner and operator of the 6,825-tonne ferry, Sewol, which capsized and sank on April 16 with the loss of around 300 lives – most of them schoolchildren.
Yoo is wanted for questioning on possible charges of embezzlement and criminal negligence, as prosecutors investigate the extent to which the Sewol disaster was caused by a lack of safety standards and regulatory violations.
“We hope the bigger cash reward will lead to his quick arrest,” senior prosecutor Kim Hoe-Jong told AFP.
Yoo has no direct stake in Chonghaejin, but his children and close aides control it through a complex web of holding companies.
His current whereabouts are unknown and a warrant was issued for his arrest after he failed to comply with a prosecutors’ summons earlier this month.
Five Chonghaejin officials have already been arrested and a lesser reward of 100 million won has been offered for Yoo’s eldest son, Yoo Dae-Gyun.
On Thursday, investigators raided a compound belonging to the Evangelical Baptist Church of Korea, of which Yoo is a leading member, but failed to find him.
Yoo has described himself as an artist and photographer and was once convicted of fraud when a company under his control went bankrupt.