The rise of e-commerce in China has touched almost every sector of the economy – including an increasingly popular black market for DIY fire arms.
For less than $100 one can buy the parts, tools and instructions for making a homemade shotgun. There have been a number of arrests this year amid a crackdown on the practice, with police swooping on gangs of online gunrunners.
Most recently, two men from Shanxi province were arrested last month for having a small arsenal of guns, firearms parts and ammunition they had bought online on Taobao, the popular Chinese e-commerce website owned by Alibaba, which listed in New York in September in the largest ever initial public offering and which later today releases its debut set of results as a listed company.
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Police said the suspects had bought and sold gun parts and bullets on Taobao, and used QQ, an online chat app owned by Tencent, another Chinese internet giant, to find clients and give online tutorials.
Online trading in illegal fire arms has soared in the past three years, according to Ma Ding, dean of the Institute of Network security at the People's Public Security University of China, which trains elite police officers.
"The internet has provided a more convenient channel through which buyers and sellers far away can reach each other," she said. "There is now easier access to the materials and components."
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However, Ms Ma added that the quality of the weapons sold online was generally low and that military fire arms were seldom found online.
Most of the guns are basic – in one recent case, a car mechanic named Zhou was arrested in Jiangsu province for making modified air rifles designed to shoot bullets. He apparently had a fondness for bird hunting and police described his contraption as capable of "shooting a hole in a beer bottle 6 meter away".
But some online arms dealers are larger scale. In June, a man in the town of Dezhou in Shandong province was arrested for running an online shop on Taobao where he had sold an estimated 130 rifles as well as gun parts to buyers in 22 provinces worth over Rmb 40,000. He also published an online video tutorial on how to assemble guns.
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Alibaba is particularly exposed because virtually all small online sellers in China use Taobao as a marketplace. While Alibaba has strict policies prohibiting weapons sales, it has had problems policing sellers of everything from fake goods to uranium and other materials that can be used to make nuclear bombs.
"Taobao Marketplace is an open, user-generated content platform," the company said in a statement," and has stringent product listing policies in place prohibiting the listing of any firearms or weapons; the platform will co-operate with law enforcement authorities to remove problematic product listings promptly."
In most cases, gun traders have hidden from authorities and online moderators by selling innocuous sounding parts, which can then be assembled into finished guns.
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In the Shandong case, "Huo" ran a Taobao shop called Chengxin Qidong, or "Honesty Pneumatic components".
Police said it was impossible to tell from his wares that he was in fact selling guns, which are mainly assembled from components freely available in shops.
"Internet gun traders may be quite discreet, as they divide their shipments and there is nothing suspicious of the parts themselves" said Ms Ma. However, she said, police units have begun monitoring forums and online stores advertising certain types of tubing and other parts that can be used in assembling fire arms. "The cases are too difficult to crack" she said.