Police in South Korea arrested 215 people in an investigation into a suspected 325.6 billion won ($232 million) cryptocurrency investment scam, Yonhap reported.

The Gyeonggi Southern Provincial Police Agency’s Anti-Corruption and Economic Crime Investigation Unit said the arrests included staff from a fake investment consulting firm and an unidentified YouTuber with 620,000 subscribers. Gyeonggi is a South Korean province that surrounds the capital, Seoul.

Between December 2021 and March last year, the scheme allegedly defrauded more than 15,000 people by promising high returns from investments in virtual assets. Targeting mostly middle-aged and older people, it promised 20x returns and encouraged people to sell their apartments and take out loans to fund their investments.

The investment itself included 28 different tokens, six of which were created by the group. The remaining 22 had low trading volumes and were determined to have little value.

Twelve of those arrested remain in detention, including the YouTuber, who also headed the consulting firm. He initially fled South Korea to Australia via Hong Kong and Singapore.

The report did not give the names of those involved.