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.
Prostitution, illegal gambling and drugs were once the prime domain of triad foot soldiers, but immigrants have begun to carve out their own large slices of those lucrative marketplaces. In recent years, triads on the front lines are "finding it difficult to survive," Kwok said.
So gang members are turning to other pursuits, she said—and that might partially explain their alleged involvement in attacks on protesters.
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One popular scheme for low-level triads is to buy up all of a limited resource, such as the newest iPhone or concert tickets, and then sell it at exorbitant prices online, Kowk said. In fact, the Triads are the major way for normal fans to get tickets to see some of Hong Kong's most famous singers, she said.
Junior triad members have entered the delivery business, offering lunchboxes at Hong Kong construction sites, she said. "The one thing to remember about the triads is they will work with anyone to make a buck," Thrall said.
Kwok noted that it's difficult to pinpoint triads' financial standing since there are no reliable figures on their funds or other holdings.
According to Thrall, high-ranking triad members also work for the Hong Kong government, which the protesters have largely opposed as corrupt.
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Although their reasons may be in doubt, thugs shown in videos and photos are clearly triad members, Thrall said. Identifying their dyed hair and choice of apparel, Thrall told CNBC that the men accused of physically attacking the students are at the very least aspiring triads, if not full-fledged members.
Still, he said, the attacks do not seem as brutal as those conducted by real triad street fighters.
"It very much looks like a pantomime—like they don't really mean it," Thrall said, adding that "someone's put these guys up to it."