By BILL HUTCHINSON, ABC News

(DENVER) — A private security guard jailed on suspicion of murder charges claims he fatally shot a U.S. Navy veteran in self-defense during a weekend confrontation that erupted amid opposing protests by right- and left-wing groups in Denver, according to his attorney.

Matthew Dolloff, 30, who was working as a bodyguard for a local TV news crew, claims he feared for his life and opened fire when the alleged victim reached into his shirt, his lawyer, Doug Richards, told the Associated Press.

“He was doing what he was supposed to be doing there,” Richards said of Dolloff, who was hired to protect a KUSA-TV news crew covering dueling protests on Saturday in a courtyard near the Denver Art Museum and just several blocks from the state Capitol Building.

Lee Keltner, 49, was shot to death in the confrontation with Dolloff, according to the Denver Office of the Medical Examiner. Keltner’s death was ruled a homicide.

Police raced to the scene of the shooting and immediately took Dolloff into custody at gunpoint. Dolloff is being held in jail pending the outcome of a homicide investigation, according to the Denver Police Department.

Denver investigators refuted rumors that Dolloff was a member of Antifa, a militant left-wing political movement.

The shooting unfolded at 3:37 p.m. local time following a “verbal altercation,” Division Chief Joe Montoya of the Denver Police Department said at a news conference Saturday evening.

According to a police affidavit supporting an arrest warrant for Dolloff on one count of first-degree murder, Keltner was leaving a rally organized by a right-wing group when he ran into Dolloff.

“Both men yelled and postured, leading several witnesses … to believe the men may engage in a physical altercation,” causing one witness to try to separate the men, according to the police affidavit obtained by ABC News.

Photos of the incident taken by a photographer for the Denver Post showed Keltner initially appear to slap Dolloff in the face. Other photos taken by the Post photographer showed Dolloff drawing a semiautomatic handgun and aiming it at Keltner, who appeared to be spraying a can of pepper spray.

In another photo, Keltner is seen splayed on the ground, a can of pepper spray next to his body, as Dolloff continued to point his gun at him.

Police investigators said they also reviewed video from witness cell phones and police surveillance cameras that captured the deadly confrontation.

“Mr. Keltner strikes Mr. Dolloff in the side of the head with an open hand. Mr. Dolloff is then observed drawing a handgun from his waistband, aiming it a Lee Keltner and shooting once, striking Mr. Keltner, as Mr. Keltner discharges his OC spray,” the affidavit reads. “Mr. Keltner collapsed to the ground.”

Montoya said two guns and a can of Mace were recovered at the scene. Police officials declined to say on Monday who the guns belonged to.

“This was a very clear case of Matt acting in self-defense,” Richards told The Denver Post.

Dolloff has not been formally charged in connection with the fatal shooting.

Richards did not immediately respond on Tuesday to a request for comment from ABC News.

The shooting followed dueling demonstrations in Denver’s Civic Center Park, one organized by a local right-wing group that billed the event as a “Patriot Muster” and counterprotest left-wing organizers called a “BLM-Antifa Soup Drive.”

KUSA-TV, the NBC affiliate in Denver, released a statement confirming Dolloff was hired through a private security company to provide protection to its news crew covering the two demonstrations.

“It has been the practice of 9NEWS for a number of months to hire private security to accompany staff at protests,” KUSA said in the statement.

The shooting is the latest in a series of fatal shootings that have occurred at protests in recent months throughout the nation.

Kyle Rittenhouse, 17, was arrested and charged with two counts of murder stemming from the Aug. 25 fatal shootings of two men in Kenosha, Wisconsin, who were part of a protest over the police shooting that left Jacob Blake Jr., a 29-year-old Black man, paralyzed. Rittenhouse, who has yet to enter a plea to the charges, is being held in jail in his home state of Illinois and his attorneys have been fighting extradition to Wisconsin.

On Aug. 29, Aaron “Jay” Danielson, 39, a supporter of a right-wing group called Patriot Prayer and a pro-Trump demonstrator, was shot to death amidst opposing protests in Portland, Oregon. Michael Reinoehl, 48, who was providing security for Black Lives Matter protests in Portland, was identified by authorities as a suspect in Danielson’s death.

Reinoehl was shot and killed by authorities on Sept. 3 in Lacey, Washington, when he allegedly pointed a gun at members of a federal task force that was about to arrest him, officials said.

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