Maybe it's your hosting provider's failure ? But it looks like dos attack ))
Belive me I have every day new problem from my pacifichost.com hosting provider.

The last was -

I warned you and I will not be answering anymore of your tickets.

If you have a web host that is currently hosting your websites perfectly fine, I suggest you cancel your service with us and move the rest of your websites to them.

Belive me this is like DDoS Attack but without the finish ))

Well Good luck !