A team of hunters study the wet ground for any signs of recent movement. "I've got fresh tracks over here," yells one man. This is no ordinary tracking party. The men aren't searching for animals. Instead, they're hunting for Mexicans who have entered America illegally. In the past year this group has rounded up over 1,300 migrants. They claim to be protecting their jobs and homeland from unwelcome intruders. However human rights groups accuse them of using violence and intimidation to terrify migrants and question their authority. As Jennifer Allen from Border Action Network explains: "It is not the role of civilians to be essentially kidnapping people." There are also concerns that these groups are promoting racism. One vigilante group, American Patrol, claims that 95% of illegal immigrants are plotting to re-colonise ancient Aztec lands in America. They have produced a video warning fellow citizens about this threat. The Anti-Defamation league claims they have received financial backing from known hate groups. Another militia member tells a group of captured immigrants that they should overthrow their democratically elected leader, Vicente Fox, and start a revolution. This would result in them finding better jobs in Mexico instead of coming to America to look for work. However, despite the militias' best efforts, poor migrants will continue to risk everything for a chance of prosperity.

Produced by SBS Australia