Pro-democracy demonstrators and police in Hong Kong have blamed thugs tied to so-called "triad" gangs for recent attacks on protesters, but some experts say the underworld gangs' far-flung business ventures make any motives for violence unclear.

Popular myth says that the Tiandihui was founded in the 17th century to fight against the Qing dynasty. Members of the group, the story goes, were patriots who fought in secret for the good of the people. Now, interviews with protesters and other media reports accuse Triad gangs of harassing protesters in Hong Kong—allegedly in concert with authorities.



But the idea that Triad thugs are operating out of sympathy with Beijing does not hold water for Triad researcher Sharon Kwok of City University of Hong Kong, who told CNBC that it probably all comes down to money.

"I don't think they would say they are supporting the government, or their political ideology," Kwok said. "It's very likely that someone paid them to do it."



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On the other hand, it's questionable whether the effort would even be worth their time. The triads make up a massive criminal underworld, believed to encompass tens of thousands of members across several distinct organizations, with interests in casinos, transportation and finance. So some experts have questioned why such a network would have a monetary incentive to harass teenagers.

"A triad is far more likely to make their money in the stock exchange these days than robbing old ladies in the street," said Chris Thrall, whose book "Eating Smoke" recounts his former personal association with the 14K Triads.

Kwok said, however, that triad moneymaking schemes vary across different levels of the gangs. Leaders "have a lot of resources from the past to infiltrate legitimate businesses," such as property development and casinos in Macau, but lower-level members face an increasingly competitive market for vice in Hong Kong.