Members of the group, said to be wearing backpacks, secretly traveled to northern Mexico... Secretly? Apparently not.
Which makes what Gertz says above, hyperbole.
BTW, wouldn't a bunch of Caucasians walking around Mexico in mid-July, look funny.
Don't embarrass yourself by grade school confusion over the meaning of "Caucasian" (IE white racial type); and "from the Caucasus region."