I've seen other reports of this incident. Not the first murder of this sort it seems.
Apparently the man arrested is a forty-year old Eritrean and there was no connection between him and the victims. The motive for the attack remains, at the moment and perhaps for some time to come, unknown.
The German authorities, I note, were, to their credit, quick to set up a help-line offering counselling to witnesses who may have been affected by the incident.
Germans who may be alarmed by AfD's cynical exploitation of this incident should be reminded that the average German is far more likely to die because of an electrical fault in his toaster than being pushed under a high-speed train by an asylum seeker.
Have I got the narrative correct?