Yet another sign of impending danger?

Some months ago, I posted about the sudden and dramatic fall of the Argentinian stock market, including one of its largest banks (BMA). Today we look at a stock from the Hong Kong exchange. Artgo is no BMA, but neither was it a speculative IPO. The important thing I am trying to show here is now we are outside of the singular market of Argentina and a stock has dropped 99% in a matter of minutes. One might want to ask the question, how is this possible and is the US market really safe from these sorts of plunges?

Disclosure: I am short the HK and Chinese exchanges via FXP.