I agree, Morgana. These attacks seem mindless but presumably they do have a purpose - to foster rage and retaliation against the Muslim community which might, in turn, drive them into the arms of the extremists. Blaming all Muslims, or all migrants, plays straight into the hands of those who perpetrate these terrible deeds. I think that the contributors to this forum have more sense than to lump an entire community together and label them all as murderers, but unfortunately not everyone is so restrained. It is also true that international politics has played its part in radicalising people. God knows how much terrorism can be traced back to the war in Iraq.
As for this particular incident, the man seems to have been a petty criminal, though I suppose he might turn out to have terrorist links. I wonder, though, how many violent and embittered people decide to link a political/religious message to their own private grudge against the world.
Whatever his motivation, it was an appalling thing to do. Those poor, innocent people...and so many were children.