The defenders of Slavyansk have reported casualties - three militia, two civilians. Also they say that any messages about the city being captured are lies, the fight still goes on.
Yet, even if they are wrong, it's kinda early to relax.
Just like you, I wish it was fake. However, I doubt it.
If it's real, I must remind that all these people used to be (or even remain) the citizens of Ukraine (wasn't this guy a former "Berkut" leader?).