Bitfinex did not report anything to the Hong Kong police. They lied. There is no investigation from any authority yet.
You can call yourself the police from HK and they will confirm you that.
Well, that's no surprise. Bitfinex is interested in brushing this under the rug, not introducing more law enforcement agencies. They have said that the FBI and some European law enforcement agencies are investigating -- if you want to believe that.
I am more curious about the FBI or US Attorney's investigations into Bitfinex's actions. You can't serve US customers then flout US law. That will get your site shut down and bank accounts seized.