Asian police forces are ramping up their attacks on unauthorized betting operators as the 2018 FIFA World Cup draws to a close.

Authorities in China’s Guangdong province announced Wednesday that they’d arrested 540 individuals involved in a massive online football betting operation that reportedly handled a spectacular RMB10b (US$1.5b) worth of wagers from over 330k customers, who primarily used Bitcoin as gambling currency.

According to the state-run Xinhua media outlet, police took notice of the operation in May, and their subsequent investigation revealed that the operation had been active for eight months. Police identified six key individuals among those arrested who oversaw more than 20 regional operations in southwest, central and southern China.

In addition to the arrests, police seized RMB5m in assets and another RMB10m worth of virtual currency. The gang operated some 70 mobile apps and websites, which were promoted via 250 online chat groups, which have since been shut down.