The answer to this actually depends on country you are living in , if your country supports bitcoin and it is legal to use in market then you can contact cyber crime department simply and they will try to help you,but if you are living in a country where its not yet illegal or legal ,then there is no way out to you can get your bitcoin back,this is because a cyber crime department will only work if something is legal in your country and is being used very often for eg:-  online transaction taking through banks, your thing not being legal will not be matter of concern for them and reporting them can act as boomerang and they can stop  you from using all this.