The fact that no physical descriptions are mentioned probably answers your question.
I always operate on the same basis of reasoning and deduction. If the often politically correct authorities let loose something like this to the general public that something strange is afoot, that means somebody saw it, and saw it in multiple instances, and has a description of the suspects or persons of interest. Yet they don't release the description of the persons of interest...hmmm. Put two and two together. Just like how the D.C. papers in English do not report that certain gang machete attacks have suspects who are Hispanic, but the Spanish language papers put in there clearly that the suspects are "Hispanico". This political correctness unnerves me no end. Give us all the facts, FBI.