Denver authorities on Sunday identified the security guard who was arrested after a fatal shooting near dueling protests by left-wing and right-wing demonstrators.
The Denver Police Department said in a statement that Matthew Dolloff, 30, was being held for investigation of first-degree murder in a shooting Saturday outside the Denver Art Museum that left one man dead.
Jail records show that Dolloff was being held without bond.
Authorities have not identified the victim of the shooting. The protests had taken place earlier at Denver's Civic Center, where people had gathered for a “Patriot Rally” and a Black Lives Matter-antifa “soup drive.”
NBC affiliate KUSA reported that it had retained Dolloff as a private security contractor through Pinkerton, the risk management and security services firm. The outlet said it had begun using private security in recent months while covering protests.
In a statement Monday, Pinkerton described Dolloff as a contractor "from a long standing industry vendor." The company said it is cooperating with a police probe investigating the incident.
The Denver Police Department had said Dolloff was acting “in a professional capacity as an armed security guard” for a local media outlet at the time of the shooting.
Eric Escudero, a spokesman for the Denver Department of Excise and Licenses, said late on Sunday that while Pinkerton is licensed to employ security guards in the city, there was no record of Dolloff himself having a license, as is required.
"If he was operating as a security guard, he was in violation of the law," Escudero said in an email, noting that Dolloff could be fined up to $999 and face a year in jail. Pinkerton could also face administrative action, he said.
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After the shooting, social media posts linked to Dolloff to the anti-fascist movement, but in an apparent response Sunday, the police department said it was “unaware of whether the suspect is personally affiliated with any political organization.”
A lawyer for Dolloff, Doug Richards, told KUSA that Dolloff was acting in self defense when he opened fire.
"This was not a political assignment for Matt," Richards said. "This was simply Matt protecting your employee."
The Denver medical examiner's office identified the victim Monday as Lee Keltner, 49. His son, Johnathon Keltner, told the Denver Post that his father "wasn't part of any group" and attended the protest to support the police — something he'd done before.
The newspaper reported that Lee Keltner was a U.S. Navy veteran who ran a hat-making business in the area.
A Denver police official, Joe Montoya, said Saturday a verbal altercation preceded the shooting, which occurred as the protests were winding down. Photos of the confrontation captured by a Denver Post photographer appeared to show a man spraying something at another man with a handgun.
Montoya said that video had been recovered, but he declined to provide details. He said two guns and a can of Mace were found from the scene. He said investigators were still trying to determine what happened.
"We don't want any erroneous information going out, any speculation, because that's really what hurts us, and that's what gets everybody angry and motivated to commit more violence, and that's what we're trying to prevent," Montoya said at a news conference.
Helen Richardson, the Denver Post photographer who photographed the shooting, said in an Instagram post that “this thing whole thing just saddens me beyond words.”
"I fear for what the weeks ahead hold for all of us," she said.