A Vietnamese court has convicted 91 people over their involvement in a US$420 million online gambling syndicate, including the public official who was supposed to be enforcing rules against online betting.

Nguyen Thanh Hoa, 60, the then chief of the “high-technology department” at the Ministry of Public Security, was jailed for 10 years  on a charge of abusing his power while performing an official duty.

Known for his tough stance on internet gambling, Nguyen had closed down hundreds of sites linked to illegal football betting before his arrest in March, AFP reported.

Phan Van Vinh, the former head of the police general department, was given a nine-year jail term on the same charge. He was admitted to hospital with high blood pressure and did not attend the sentencing.

“(Vinh) caused discontent among the public and distrust of the police force,” judge Nguyen Thi Thuy Huong was reported as saying.

Other defendants were fined or sentenced to house arrest in the three-week trial in northern Phu Tho province, which ended one of the biggest illegal betting operations seen in Vietnam. Most forms of gambling are banned in the country, but illegal betting is rife.

President Nguyen Phu Trong, who leads the ruling Communist Party,  is personally overseeing a campaign against corruption. Vietnam was ranked 107 out of 180 countries in Transparency International’s Corruption Perceptions Index.