What really happened in chaotic Sarajevo in and around Dobrovoljacka Street on 3 May 1992?

The range of views appears to be broadly as follows:

Core Serbia/’Serb’ Claim:   perfidious massacre of JNA soldiers attempting to withdraw from Sarajevo under UN colours as per an agreement duly reached with the Bosniac leadership, with senior Bosniac leaders including Ejup Ganic personally responsible either directly or implicitly. Slam dunk war crime.

Bosniac Claim Version 1:   understandable formal military response to previous JNA brutality and kidnap of President Izetbegovic – JNA themselves broke the agreement under which they could withdraw. That said, not known who gave the orders to shoot. No war crime – chaos of war, which Serbia started

Bosniac Claim Version 2:   spontaneous, irregular but more or less understandable/justifiable attack by Bosniac irregulars responding to JNA aggression the previous day. No formal orders given. No war crime – just a mess

Bosniac Claim Version 3:  a fully legitimate attack on a fair military target: at worst the Bosniacs were in ‘technical’ breach of a ceasefire unfairly imposed on them as a condition for getting back their kidnapped leader. Even if orders were given, as it was a proper military attack the issue is of no significance. No issue here folks, so move along

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The Serbian claim lies behind the Serbia government’s latest attempt to secure Ganic’s extradition. But what level of hard evidence will they need to put forward (a) to make a convincing and finally winning case for extradition now, and (b) to secure a conviction if the issue ever gets to trial in Serbia?

The Death of Yugoslavia videos suggest different version of Bosniac Versions 1 and 2, as articulated by Ganic himself and others. For a good, detailed account of the "it was all a mess" approach, read this interview with Jovan Divjak, one of the few people in the whole Yugoslav collapse disaster to have kept a reputation for integrity:

You believe that there was no order to attack, that it happened spontaneously?
Absolutely spontaneously.
 
Could it have been avoided?
Of course. Why did the JNA attack Sarajevo on 2 May? What was the JNA doing in Sarajevo on 2 May? It was a general test to see how the Territorial Defence, police and others would react. They did not have to arrest Alija Izetbegovic. None of this would have happened if Izetbegovic not been taken prisoner. Were it not for this, I am certain that after a while and through negotiations the siege of all the barracks would have been lifted without a shot being fired.
 
… I was there and saw that it was not organised. I repeat, some people did try to attack the JNA. They were saying: ‘Let’s go, let’s move, let’s proceed bit by bit.’ It was not a command. The commanding officers’ command was: ‘Don’t go, wait, don’t attack, don’t shoot.’ The commanders of the basic units tried to prevent shooting.
 
And for the hard-core Bosniac view that it was a legitimate military action, try this piece by Marko Attila Hoare:
 
The ability of Bosnia’s defenders to defend their civilian population from the Serbian genocidal attack depended largely on their ability to recapture their weapons from the JNA – their attacks on the JNA in Sarajevo and Tuzla were a matter of life and death.
 
… Fifteen years after the end of the Bosnian war and ten years after the overthrow of Miloševic, Serbia is still hounding Bosnians who attempted to resist its aggression and genocide in the 1990s. Such behaviour is of a kind with the Serbian parliament’s unwillingness to recognise the Srebrenica massacre as an act of genocide, despite the fact that this genocide has been recognised by two different international courts.
 
Quite how the London courts will try to pick their way through this mass of fundamentally irreconcilable views remains, as they say, to be seen.