I heard on FOX that one of those arrested was an American, who I’m guessing is either black, or a Muslim with US citizenship.
I hadn’t read there was an American. You are right, I’m finding it too.
http://www.jammiewf.com/2016/two-cologne-marauders-arrested-carrying-notes-in-german-and-arabic-saying-i-want-to-have-sex-with-you-and-ill-kill-you/