
Dressed in camouflage gear and wielding heavy machine guns, these men look like they are off to war.

But while the pictures appear to show this band of brothers patrolling a conflict zone, they are actually guarding the border between the US and Mexico.

The ‘watchmen’ of The Arizona Border Recon - led by the group's chief 'Nailer' - protect the border near the Mexican town of Nogales, with three goals; stop illegal immigration, stop drug smuggling, and stop human trafficking.

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Patrol: The Arizona Border Recon guard the US-Mexico border, dressed in camouflage gear and wielding heavy machine guns

The line: Led by the group's chief 'Nailer' - the band of brothers protect the border near the Mexican town of Nogales. Pictured, America, left, and Mexico, right

The ‘watchmen’ of The Arizona Border Recon have three goals; stop illegal immigration, stop drug smuggling, and stop human trafficking

Research: The team use Google Earth to mark possible meeting points for migrants and criminals trying to cross the border

The striking photographs of the Arizona Border Recon (pictured) were taken by Johnny Milano for his project The Hills of Pima

Always on guard: Group chief leader Tim 'Nailer' Foley surveys the hills, using binoculars as he keeps an eye out for activity

The striking photographs were taken by Johnny Milano for his project The Hills of Pima, capturing the men's 24-hour operation which sees them monitor the border, watch carefully for immigrants and stop cross-country criminals in their tracks.

They look like soldiers - and some of them are veterans - but many are or were private security experts, Mr Milano told Feature Shoot.

This means that they do not necessarily have the power to stop people attempting to make into the U.S., but this does not stop them from taking action.

Technically speaking anyone can perform a citizen's arrest, but illegal immigration and human trafficking are not day-to-day offences.

'I think “authorization” becomes a complicated term in this sense, Mr Milano explained. 'It becomes complicated because although the state may give legal authority to do so, this is actually an international policy issue concerning inter-country borders, not something like a bank robbery.'

The men consider the gradual wave of Mexicans and others crossing the border as 'an invasion' - similar to many of their tours with the US Army.

Old guard: The men look like soldiers - and some of them are veterans - but many are or were private security experts

The group do not necessarily have the power to stop people attempting to make into the US, but this doesn't stop them from taking action

The men consider the gradual wave of Mexicans crossing the border as 'an invasion' - similar to many of their tours with the Army

US Customs and Border Protections does not appreciate the Arizona Border Recon (pictured on a night time mission), the photographer said, at least at federal level

The US-Mexico border (pictured at Sasabe, Arizona) is not a new political issues, but it is a growing one. Donald Trump has vowed to build a huge wall along the entirety of it

Mr Milano said: 'To them this is most certainly an invasion. In some respects I believe the US/Mexico border is the nearest domestic geographic place where many of the vets can compare to their tours in Afghanistan or Iraq, or elsewhere, so in some way it is the easiest way to get back into “protecting the country” from what they believe is the most imminent threat and performing their civic duty.'

US Customs and Border Protections does not appreciate the Arizona Border Recon, the photographer said, at least at federal level.

But he said that officers on the ground welcome intelligence the men have picked up on their patrols, especially when visiting houses along the border.

The US-Mexico border is not a new political issues, but it is a growing one. Donald Trump has vowed to build a huge wall along the entirety of it.