May not be a reliable source.
The German government has had its refugee policy blow up in its face, and is desperately trying to work this into something that isn't their fault. I'm afraid Heiko Maas is part of the problem.
Also doesn't easily explain the similar events all across Europe, although it's interesting to see someone in government trying to rejigger individual actions into a huge jihadist conspiracy for a change.
From CNN:
Thirty-one people, most of them North African or Middle Eastern countries, have been charged in the attacks. Of those, 18 have been identified as asylum-seekers.
"Recent arrivals." 18 out of 31 so far.
In Helsinki and Sweden: more "asylum seekers."
You realize it makes no difference in the fundamental issue of mass immigration whether this is a Europe-wide conspiracy of infiltrators hidden among real refugees, or just the random unpleasant nature of a particular culture.