Nope. They're never comment their shutdowns in their Twitter.
That is surprising. I would be worried about using or leaving my funds in a service that shutdown without notice and resumes operations like nothing actually happened. That's a big red flag.
Because this is not a Russian exchange. I'd lost some BTC on WEX in the past. While Tradeogre is in USA, so I believe them more.
I think it's a technical issues. But this excnahge was never offline so long time.
For whatever it is worth, it does not matter where a centralized exchange is registered, not your keys, not your coins still stands. However, that matters less to you right now, and for your sake and others who have funds in there, let us hope it is one long technical issue.