Nearly 100 police officers from the Ministry of Public Security and HCMC on Tuesday raided 10 locations in the city and arrested 11 members of the ring, including the kingpin Nguyen Hoang Long, 39.

The raids, which included on a bank on Hung Vuong Street in District 5, also netted over VND4 billion and $100,000 in cash, a number of luxury cars and equipment and ledgers used for the gambling.

According to investigators, in late 2017 Long established several apparently legitimate companies in many different fields as a front for his activities.

He then rented offices in several districts in the city and installed and connected equipment to football betting site bong88.com.

His henchman Nguyen Quang Hai, 39, was responsible for managing the ring's activities and its dozens of employees and technicians in Vietnam.

Investigators have estimated the total value of the ring's transactions at around VND3 trillion based on data from thousands of gambling accounts in which tens of billions of dong worth of transactions were done every week. (VND1 billion = $43,000).

The police are investigating, and have issued summons or arrest warrants to a number of people allegedly involved with the gang.

Vietnam legalized betting in 2017, allowing on a trial basis people aged over 21 with a monthly income of at least VND10 million ($432) to gamble in a casino on the southern Phu Quoc Island.

But all other forms of gambling remain illegal.