The illegal rings contained 113 bookmakers, which had accepted bets worth over ₫2tn (US$86m). A number of the 30+ group were arrested, while others were brought in for questioning.

Pham Cong Bang, 29, has been identified by officials as the main leader of the gang. The police found out the gang had been operating from a rented house in Thai Binh Province.

According to the authorities, the suspects had opened accounts with foreign gambling websites, serving as agents for them within Vietnam.

Those who chose to gamble through the illegal online rings would use virtual money to play and convert winnings into real money.

The arrests stem back to January, when the police had frozen many of the gang’s bank accounts.

In 2017, Vietnamese authorities legalised sports betting for citizens aged over 21 with a monthly income of at least ₫10m and allowed them to play in a casino in the southern Phu Quoc Island.

Online gambling in Vietnam, however, remains illegal.

In April, Vietnamese police raided and shut down an illegal online gambling ring which handled more than US$1bn, arresting 22 people in the process.