Federal prosecutors charged a Minneapolis man with illegally buying and reselling one of the pistols used in a gunfight this month that left one dead and 14 injured inside St. Paul's Seventh Street Truck Park bar. Jerome Fletcher Horton Jr. has bought 33 guns since mid-June, including many that investigators say he illegally sold to others, according to a Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) affidavit unsealed Tuesday.

Authorities found one of the guns — a 9-millimeter semi-automatic pistol — stained with fresh blood inside a vehicle, according to the ATF affidavit. Authorities found the vehicle after surveillance footage showed a suspect getting into its back seat after the bar shooting, and some of the shells found on the bar floor matched the weapon.

Horton is charged with buying a firearm and illegally selling it to another person. This practice, known as "straw purchasing" or "lying and buying," is a primary driver of how illegal guns are flooding the streets and driving violent crime rates in the Twin Cities, federal authorities say.

The gunfight Oct. 10 near downtown St. Paul was the city's largest mass shooting in recent history. The shots rang out just after midnight, sending patrons rushing outside and killing 27-year-old Marquisha Wiley.

The St. Paul Police Department identified one of the shooting suspects, according to charging documents, and surveillance footage showed him leaving the bar with a firearm and getting into the vehicle, where the 9mm gun was found.

The ATF traced the gun to Horton, who had bought it and two others at a Fleet Farm this summer. Horton also bought guns at Frontiersman Sport in St. Louis Park, where employees said he raised their suspicions. After one purchase, according to the ATF, surveillance footage showed Horton waving the gun boxes in the air to people waiting outside the store.

The ATF searched Horton's home but found no guns. Horton denied straw-buying the guns, but he admitted to selling seven weapons to four people, according to the ATF. He first told investigators that some of the guns had been stolen, then said they'd been taken from a stash location at the Lamplighter Lounge strip club in St. Paul.

Horton, who made his first appearance in U.S. District Court on Tuesday, was being held in the Sherburne County jail.

Straw buying is an illegal way to obtain guns by someone prohibited from possessing them because of their criminal past. The practice is difficult to prove, which is why only a small fraction of straw buyers face consequences. This summer, the U.S. Attorney's Office in Minnesota charged a woman with illegally straw buying 47 guns in a month; some of the weapons turned up in shooting investigations weeks later.

Horton is the third person charged in connection with the mass shooting. Also charged were Devondre Trevon Phillips, 29, with 12 counts of attempted second-degree murder, and Terry Lorenzo Brown, 33, with one count of intentional second-degree murder and 11 counts of attempted second-degree murder.

Andy Mannix • 612-673-4036