The Belkan States shall look into the Russian mafia to make sure they had nothing to do with the heinous crimes on your country.

We have already performed inquiries into the mafia and it is very unlikely that they were the bombers. For starters, they're covert in their operations, they choose to smuggle in items that more for personal use rather than on such a large scale and they try to only sell items that cannot be traced back to them. However, if you are using agents we would recommend directing them towards the black market to listen out for any who are selling weapons on a massive scale or are selling explosives. It'd also be best to stick to your homefront as so to prevent further incident.