Well, this wins for silliest non-alien theory, with bonus points for the hyperbole of “concentration camp” to describe illegal immigrant detention.
It's not labour camps, and not extermination camps, but rather places where people are 'concentrated' while the bureaucracy figures out where to move them next.
If anything it's really weird to present it as having to do with supposedly illicit immigration, since citizens and people with residence permits are vacuumed up as well.