There were many war crimes in Sarajevo, but this one is probably fake. The only evidence for this is some shady testimonies, and it was not backed up in post war testimony of soldiers, flight logs, etc., even though many other war crimes were.
Maybe get yourself acquainted with a topic before you throw up something like this. For reference here is a video of renowned russian poet Eduard Limonow, shooting at Sarajevo: https://www.youtube.com/watch?v=JkjPZvz27mg . I guess this video and the "little" fact that the Italian state prosecutor would not just open an investigation based on some hear/say should make it a bit more believable, shouldn't it?
Limonov was here for ideological reasons. All sides had foreigners in their ranks of various motivations, from the mercenary and the adventurer to the strongly ideologically motivated. What is missing is evidence of people coming there for pure entertainment and paying for the privilege...
Well, that's why the Italians are conducting the investigation, isn't it? No-one claimed it was proved.
Interesting video. "Poet" shooting at a city with another "poet" Karadzic. Curious that they speak English, wasn't Russian taught at schools in Yugoslavia? And Karadzic's command post being a cable car.
Russian was taught mainly in the in Warsaw Pact countries. Yugoslavia was never in the Warsaw Pact.