A comment on a New York Times article about violence towards doctors in China reads:
The situation is explosive. In 2010 there were 17,234 cases of violence against medical personnel reported by CCTV. Hired thugs called "niyao" beat up or kill doctors for 100 yuan ($16 US) plus cab fare. China Daily says attacks increase 20% per year.
I could not find the characters for "niyao" anywhere or a definition of a "niyao" as a strong-armer. Can someone point me to a source?