China's internet vigilantes and the 'human flesh search engine'
Last month a Chinese official in charge of internet surveillance gave notice that mobs of web users who turn on individuals and make their lives a misery will not be tolerated. In China it happens often and on a massive scale, earning the phenomenon the title of the "human flesh search engine".
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Earlier that day, they told him, a driver in Urumqi had rolled down his window to spit on an elderly homeless person lying on the street. Witnesses recorded the first few digits of the spitter's licence plate. The information was quickly broadcast by a local radio station.
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Hours later, they zeroed in on Yin, whose licence plate was a partial match and posted his mobile number online.
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"All of my private information was made public. My ID card number, name, phone number, address, even my mother-in-law's phone number was dug out and posted online," Yin remembers. "I even received phone calls blackmailing me, threatening to burn my house down if I didn't pay them 200,000 RMB [$33,000; £20,000]."
http://www.bbc.co.uk/news/magazine-25913472
Makes some of the bullying you see in western countries look tame.