They know who the people are, but if the perpetrator's home governments don't want to give them up (article refers to Ukraine) there isn't a lot that can be don

They know who the people are, but if the perpetrator's home governments don't want to give them up (article refers to Ukraine) there isn't a lot that can be done. Do we know that they aren't cooperating? No, but you can just look at the forums in question without an invitation so it's not like it would be hard if they wanted to.