Chengguan are now trying new tactics. The DEATH STARE!!!!
http://www.danwei.org/front_page_of_the ... actics.php
There is no known defenses against the mass use "Evil Eye"
Also, Chengguan crackdowns in Beijing last summer before the Olympics were pretty common. Second night in Beijing I witnessed a hard crackdown by chengguans on a middle aged lady. They smacked her around quite good.
At the time this took place I was getting out of a taxi in Wudaokou with a beer in hand. I thought the police were coming for me. Turns out they just wanted to confiscate the lady's wide variety of socks. And you know the chengguans are all wearing those "hello kitty" shanzhai socks down at the station.