CHICAGO (CBS) — Three U.S. Army soldiers who took an oath to defend this country stood charged Tuesday night with running guns to Chicago.

As CBS 2’s Charlie De Mar reported, some of those weapons were linked to a recent mass shooting.

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Demarcus Adams, 21; Jarius Brunson, 22; and Brandon Miller, 22, were charged Tuesday with conspiracy and other offenses by the U.S. Attorney’s Office in the Middle District of Tennessee.

They are accused of funneling guns back to the city from Fort Campbell on the Kentucky-Tennessee line where they are stationed.

The three soldiers were arrested Tuesday morning by agents from the Bureau of Alcohol, Tobacco, Firearms and Explosives and the U.S. Army Criminal Investigation Division.

The investigation began on March 26, when Chicago Police were called for a mass-shooting at a pop-up party on 79th Street near Campbell Avenue in the Southwest Side’s Wrightwood community.

The shooting happened at a storefront at 2515 W. 79th St. People were gathered for a celebration of life for a man who was the victim of gun violence.

One man was killed in the shooting and seven others were injured.

Multiple guns were recovered at the scene during the investigation, and five had been found to have been purchased recently from Federal Firearms Licensed dealers in the Clarksville, Tennessee area, prosecutors said.

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Further investigation identified Adams, Brunson, and Miller as the majority buyers for the guns, prosecutors said.

Michelle Chambers’ son was shot in the abdomen with one of those illegal weapons, according to federal prosecutors.

“I’m so tired of this,” Chambers told CBS 2’s Meredith Barack shortly afterward.

A broader investigation into firearms transaction records found that since September 2019, the three soldiers had bought 91 guns in Clarksville; Oak Grove, Kentucky; Hopkinsville, Kentucky; Fort Campbell, Kentucky; and Paducah, Kentucky, prosecutors said. Most were purchased in the last five months, prosecutors said.

A criminal complaint claims once the soldiers bought the guns, Miller gave them to people with whom he was associated in Chicago.

A federal search warrant was executed at Miller and Adams’ Clarksville home on Wednesday, April 28, and 49 empty gun cases were found, prosecutors said. Many of the empty gun cases matched to guns recovered by Chicago Police at the scenes of recent shootings and homicides, prosecutors said.

The criminal complaint issued late Monday charged all three soldiers with transferring a firearm to an out-of-state resident; making false statements during the purchase of a firearm; engaging in the business without a firearms license; wire fraud; money laundering; and conspiracy to commit Title 18 offenses.

The suspects appeared before a U.S. Magistrate judge in Nashville Tuesday afternoon. If convicted, they could face up to 20 years in prison.

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CBS 2’s Charlie De Mar is working to learn more on this case. Look for his story on the CBS 2 News at 10.

Charlie De Mar