Now the important thing here is to not overreact!
It is "only" BTCCHINA and not BTCC - which operates international and the mining pools are also not affected.
However - it does raise the question: What now?
1.) You could HODL and act as if nothing is happening - I can't tell you what happens, but my guess is that it will recover in some time. Could be weeks or months.
2.) Sell for Tether and buy in again, when you think the downward trend is over.
My opinion is, that it will result in a downwards trend as it only pushes the fear people have in regard to china even further.
What is your opinion?
-Wolf