Garzon is a controversial judge. He's the one who issued an extradition order for Gen. Pinochet which led to the general's being held for so long in London, until the legal case could be sorted out. But here I applaud what Judge Garzon is doing.
Garzon is somewhat of a celebrity in Spain, having worked on numerous high profile cases (and severely disrupting international law in the Pinochet affair). He's quite showy, but then, sometimes he really hits the mark, and he is not easily intimidated. I'd say he's definitely scored with this arrest.
BTW, alert readers may have noted that one of the names of those arrested was not Arabic, but Spanish. The man is indeed a Spaniard, a convert to Islam whose prior activities seem to have included some minor connection with HB, the political wing of the Basque terrorist group, ETA. Both the fact that he was a convert and the fact that he had had some contact (although possibly not extensive) with a domestic SPanish terrorist group make this report even more alarming.