Tokyo police have arrested eight people for suspected investment fraud that they say saw about 3,300 people swindled out of some 20 billion yen ($152 million).

Kota Morino, president of Tokyo investment consulting firm FRich Quest, and the seven others are alleged to have defrauded investors between 2016 and 2022 by promising high returns on their money managed through a Seychelles-based company.

The suspects had promised a 4 percent monthly return on investments and urged those who did not have money to invest to borrow from consumer loan companies, according to the police.

Many of the investors were apparently young people in their 20s and 30s, and average borrowings to invest through the purported company in the Indian Ocean country totaled some 7 million yen.

Morino's consulting firm is alleged to have taken on loan applications on behalf of the investors. The whole operation was cash-based, apparently to keep the scheme opaque and avoid scrutiny from authorities.

Employees of the firm apparently used the encrypted messaging app Signal to communicate with its investors.

But the company is said to have been teetering on the edge of collapse from around the fall of 2021, with dividend payouts halted in around January 2022.

Police allege the money collected from the investors went toward Morino's entertainment expenses and parties thrown for investors, as well as personnel costs.

The arrests of Morino and the seven others on Wednesday are linked to a fraud case in which four people, including a man in Miyagi Prefecture, were allegedly swindled out of a combined 56.8 million yen between October 2021 and January 2022.

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