This is what I think happened.


1) BTC-E noticed some security vulnerabilities, upcoming with the fork on 1st of August.

2) BTC-E shutdown their servers to check what was going on

And at the same time law enforcement was trying to arrest another guy who laundered money through BTC-E. They don't know if he is the owner of the website.

3) Law Enforcement notices that BTC-E is down and thinks that the guy their trying to arrest is them one step ahead, so they go ahead and arrest him.

4) They realize that he is indeed not the owner because the website will be up and running again soon. But he is the launderer they where looking for.