Police in Suzhou, Jiangsu province, have cracked a 5-billion-yuan (US$735 million) online gambling racket and detained a gang of 30 members, eight of whom have been officially arrested.

The illegal betting scheme was orchestrated through a Malaysia-based website -www.fun88.com - which had hired over 300 agents and enrolled more than 22,000 gamblers through three affiliates in China over the past two years.

The website saw a monthly turnover of more than 200 million yuan, raking in a total of 5 billion yuan from Chinese gamblers within two years, police said on Thursday.

Hundreds of thousands of bank accounts within China were used in the scheme, police said, adding that most part of the 5 billion yuan was "out of reach".

Police got their first break in the case in February this year, when they nabbed Wang Tianbao, 28, from his Suzhou home after spotting advertisement links of the website online.

Interrogations revealed Wang used to be a driver at the local environment protection department and was not content with his monthly salary of 3,000 yuan. He became an agent of the website in October last year, police said.

Agents like Wang extracted commissions from the money gamblers lost on the website, with the rate varying from 25 to 40 percent.

Wang had amassed about 900,000 yuan from 400 website members until he was captured, police said.

Based on his interrogation and the flow of money to his bank accounts, police managed to hunt down the three affiliates based in Shenzhen and Zhuhai of South China's Guangdong province.

Police said the three affiliates played different roles in the gambling syndicate. They were responsible for accounting, advertising and technology. To attract gamblers, the syndicate gave out free T-shirts and handed out name card clips printed with its website link.

"Basically, none of the gamblers won any money from the website," Zhou Wen, an investigating officer was quoted as saying by China Central Television Station (CCTV).

"The whole thing was a trap. The gambling system they used prevented gamblers from winning any money."

One of the website members, a bank employee, embezzled more than 10 million yuan to continue gambling after he lost all the money he had, said Zhou.

In January this year, the Ministry of Public Security launched a campaign to crackdown on online gambling, in association with eight party departments, government ministries and financial regulatory bodies.

As of June 4, the ministry had cracked more than 670 online gambling cases and purged 26 gambling organizations with overseas connections.