If you go and glean through what is said by the cops....it comes down a pretty simple story.
1. Cops are called around 4:30 AM to a disco (yes, they still exist) in the Lake Constance area (far, far south of Germany).
2. Iraqi 34-year old guy came in....automatic weapon....killed the bouncer/security guy at the door, and then peppered the disco. He then leaves. Cops intercept him at some point later (doesn't appear to be anywhere near the club). Shootout, and he's dead via the cops.
3. Cops say they had run-in's with the guy before....but didn't say why.
4. Iraqi had been in Germany since 2002....he's NOT a refugee or migrant.
End of the story via the cops. You can speculate about this. Disco operations in Germany typically have some type of drug environment going on, and ectasty is the primary drug sold. Meth has creeped up in recent years and might also be part of the dealers operation.
One might get the impression of a small-time drug-kingpin.....knocked out of entry into the club or his guys weren't allowed in to sell their stuff. He's a user of the stuff....overreacts.....does some unplanned action, and does some really stupid action.
The guy isn't a migrant or such. So far, no one can identify his occupation, and that would lead one to think he's a kingpin of some type.
End of the story? The cops will look at the weapon used and try to figure out where it came from. The gang? They will be taken aside and looked at closely. Then the cops will wrap up this report.