A North Vernon gun dealer will spend four years in federal prison for selling firearms without a license.

According to the U.S. Attorney’s Office for the Southern District of Indiana, 52-year-old David J. Mull sold hundreds of firearms illegally, without obtaining a proper dealing license. The Bureau of Alcohol, Tobacco, Firearms and Explosives sent him a cease-and-desist letter in 2016, but rather than quit, he continued to run his unlicensed gun business, authorities say.

They say he avoided detection by buying weapons from private sellers at gun shows across the country for resale. Federal firearms licenses holders are required to generate multiple sales reports when someone buys more than one gun within a five-day period. Private sellers have no such obligation to keep or maintain records.

Between 2019 and 2023, Mull sold over 500 firearms to a main customer in New York City, in exchange for about $350,000. That main customer then moved the weapons from New York to Mexico.

Acting U.S. Attorney for the Southern District of Indiana John E. Childress, said diverting firearms from legal markets in the U.S. to illegal markets in Mexico fuels cartel violence and the drug trade. He said the violence crosses borders and devastate communities.

Mull also operated an online gun sales system, selling more than 800 weapons across the country.

The Bureau of Alcohol, Tobacco, Firearms and Explosives investigated this case.

The sentence was imposed by U.S. District Judge James R. Sweeney II after Mull pled guilty to unlicensed dealing in firearms. After the four years in prison, Mull will be required to spend two years under supervised release.