In a huge clampdown by the Chinese Authorities recently, 600 people - both users and organisers - have been arrested in China, after investigating a Taiwanese based company. OVer $60 million is involved and $3 million seized.

The arrests concern both online casinos and online sportsbooks and according to China Daily an entire gambling scheme has been smashed

Preliminary investigation shows that at least 37 local gamblers have connections with Gu and they bet on different kinds of soccer matches worldwide, such as the Italian Serie A and the Football Association Premier League of England. ...Money for online gambling is mostly sent through credit cards such as Visa or through wire transfers....The data on the computers indicate that the group's gamblers had probably plunged 1.1 billion yuan (US$133 million) in gambling during the past six months, according to the Beijing Daily. Read Link

Overseas gambling, illegal lotteries and online gambling are the chief targets but the authorities are keen to distinguish between traditional entertainment activites such as the popular Mah Jong and illegal gambling