When night falls on Ferguson, Missouri, Sam Andrews gets to work.
Andrews – dressed in full camouflage and armed with an assault rifle and handgun – climbs to the roof of a dentist’s office to begin his nightly surveillance. He’s a member of the Oath Keepers, a group taking up armed positions on the streets and rooftops with the intent of protecting local businesses.
He says he’s here to defend “The best part of America, the creative part, the small businesses, the hardest working people in the United States of America. To defend them from arson.”
While some business owners are embracing the presence of Andrews and other do-it-yourself patrolmen with the Oath Keepers, many others – including police – are uncomfortable with the group’s mission.
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The group was founded in March 2009 by Stewart Rhodes, a Yale-educated attorney and former army paratrooper. The Oath Keepers claim to have active chapters in all 50 states, as well as an estimated 40,000 members – which would make it one of the fastest growing far-right organizations in the world.
The Oath Keepers’ arrival comes at a sensitive time for police in the St. Louis suburb. A grand jury last week declined to indict Ferguson police officer Darren Wilson in the Aug. 9 shooting death of unarmed black teen Michael Brown.
Following the grand jury announcement, nights of unrest followed in Ferguson, with violent protests erupting and at least 17 stores vandalized and burned to the ground.
Natalie DuBose’s bake shop, “Natalie’s Cakes and More,” was broken into and looted.
"I didn’t have the extra savings or extra money to replace everything that was destroyed,” she told ABC News following the vandalism. “The threat of not being able to take care of your children makes you feel like less than a human being.”
DuBose’s story caught Andrews’ attention. He was watching the news at home 40 miles away.
“I can’t even imagine a governor that would leave a woman like this and her business to burn, like they did,” Andrews said. “But I value this woman as much as anything I’ve ever seen in my life.”
So Andrews came to Ferguson and put out a call online for more volunteers such as himself. The Oath Keepers’ presence hasn’t been met by full support, Andrews said.
“They were calling us the KKK, they were calling us the police. We were saying ‘We’re not the police, we’re here to defend you. We’re here to defend your rights,’” Andrews told ABC News.
While the unrest in Ferguson has dissipated since last week, Andrews and his fellow volunteers say they will continue to protect the bake shop, as well as the nearby dentist’s office. Marilyn Crider, who manages Ferguson Dental, is thankful for the support.
“I don’t know where they came from, but I have to thank God they showed up,” Crider said. “We wouldn’t be standing here working today. We wouldn’t have a building.”
What separates the Oath Keepers from other militia groups is that they recruit men and women of the military and law enforcement – vowing to disobey “unconstitutional orders” from what the group sees as an increasingly tyrannical president and government.
Many, including the police, have concerns with the Oath Keepers and their mission. Oren Segal, director of the Anti-Defamation League Center on Extremism, called the Oath keepers an “extremist, anti-government group.”
“Everything that they say that stand for is based on this notion that the world and the government is going to become a dictatorship to try to prevent Americans from having their freedoms,” Segal said.
Ferguson is not the first time the Oath Keepers have made headlines. This past spring, after federal agents clashed with members of a Nevada cattle ranching family over the removal of a herd from federally-managed land, Oath Keepers and like-minded followers descended on the ranch to show their support.
Critics such as Segal have concerns with the group’s structure and viewpoints.
“When you believe that you have to arm yourself in order to protect the people from the government, and you’re such a loosely-organized group that anybody can join you, that’s a combination that can potentially create violent incidents in the future,” Segal said.
St. Louis County Police declined an interview with ABC News, but confirmed that it is investigating whether the Oath Keepers are breaking the law by providing security without a license.
But Andrews says the Oath Keepers plan to stay in Ferguson for the time being. He said hundreds of volunteers – of all races – have passed through the St. Louis suburb in recent weeks. But many of them wish to remain anonymous, preferring not to show their faces.
“We will be here just as long as it takes,” he told ABC News. “That is just the way it is.”