This photo provided by the Incheon Metropolitan Police Agency on Oct. 23, shows illegal gambling money confiscated. Yonhap

Law-enforcement authorities here said Sunday they have busted an online gambling ring based in China for illicit operations in Korea, worth a total of 5.7 trillion won ($3.9 billion).

Twenty suspects were arrested, and 171 others face prosecutors’ probe without detention, according to the Incheon Metropolitan Police Agency.

They are accused of running the gambling sites from January of 2014 until July last year through the China headquarters in charge of a server and local operating units in Korea, and presumably earning 65.7 billion won in gains, 6.7 billion of which has been already confiscated or forfeited.

Investigators said the suspects had used the server in China as part of efforts to dodge police crackdown, frequently relocating their operation sites in Korea. (Yonhap)