If you see Jews who cause harm to other Jews or Eretz Yisroel, the odds are great that they are Eirev Rav.
I seriously doubt that it’s correct to say that just because someone isn’t Frum, they are Eirev Rav. Not everyone was fortunate to have grown up in a Jewish environment and have a proper Jewish education.
If you want to get an example of the modern day Eirev Rav, look no further than those sickos in NK who go to Iran, or those that protest in the Streets of Eisav against Israel.
It’s fine to oppose the Israeli government, but it is not fine to cause harm to Jewish living in Eretz Yisroel.