Maybe someone who understands Mandarin can translate the video but the jist of initial reports that I got is that a Crime ring in China was turning airsoft and pellet guns into guns that were lethal.
There are reports that the modified guns can release 12.10 Joules of energy based on tests done at the police station. (EDIT: Although that's highly unlikely but that's what I get based on the translation, it's probably 1.210 Joules (decimal place shifted during translation maybe?))
I'm not trying to start a "the sky is falling" scare but discuss this anyways.
Also note that most guns would just explode or you could only use it once if you managed to turn an airsoft into a real firearm. Also NOTE that the guns involved were NOT purely airsoft this included pellet guns too.
EDIT: Thank you SOCINCO for bringing some context into this "story".
why this one got caught? because OCT 1st is the 60th chinese national day, the police want to show that they are working hard to make the public more safe!!!