Hong Kong police have arrested 22 locals in a crackdown on what they believed was the city’s first bookmaking and money-laundering racket that had taken advantage of financial technology to collect more than HK$500 million (US$64 million) in bets on international gambling websites.

The citywide arrests of 17 men and five women, aged 21 to 67, were made over the past weekend.

Investigators believed among those detained were the mastermind, five core members, a money changer and 15 individuals who opened bank accounts.

Chief Superintendent Frank Law Yuet-wing of police’s cybersecurity and technology crime bureau on Monday said the syndicate had paid thousands of Hong Kong dollars to people to set up virtual bank accounts that would be used to collect bets on soccer matches, horse races and online casinos offered by gambling websites abroad.

The ring members also used online game platforms, forums and social media, offering gambling tips to tempt interested parties into placing bets.

Law said the syndicate had accepted more than HK$500 million since May this year through the Faster Payment System (FPS), a platform launched by the Hong Kong Monetary Authority in 2018 to enable users to make real-time cross-bank payments.

The accounts were also used for suspected money-laundering activities.

Investigators froze more than HK$10 million worth of assets in the operation, including HK$3.4 million in cash, five luxury watches costing HK$1 million and a Porsche SUV.