CHICAGO (CBS) — One Chicago man is in federal custody, and another is on the run, after more than 350 firearms were stolen from a UPS distribution center in Memphis, and later turned up in south suburban Midlothian.

Taveyan Turnbo, 18, was arrested in Midlothian on Sunday, after he and an accomplice were spotted in a U-Haul filled with stolen guns. Roland Jackson, 24, is still on the loose.

Federal prosecutors Turnbo has been charged with possession of three stolen firearms, and Jackson has been charged with illegal possession of three firearms by a convicted felon.

On Friday, the UPS distribution center in Memphis received 16 pallets of guns from a Ruger factory in North Carolina, according to the charges against the pair. On Sunday, a few hours before a semi-trailer carrying those guns was scheduled to leave Memphis for Texas, an alarm went off at the distribution center when an unauthorized U-Haul van drove onto the lot, and two men stole three pallets of guns and loaded them into the van.

UPS officials told federal authorities the three pallets contained 367 guns, including .22 caliber and .380 caliber firearms.

CBS 2 has learned Turnbo and Jaackson rented the U-Haul on the South Side of Chicago at least three weeks ago, but they never returned it.

Police seized stolen guns from this U-Haul van in Midlothian.

Sunday afternoon, the U-Haul was spotted outside a Walgreens store in south suburban Midlothian. A caller reported two men selling drugs from the truck. Sources told CBS 2 the men were actually selling the stolen guns. According to the charges, Turnbo and Jackson sold at least three guns for a total of $400 before they were arrested.

When officers arrived, they questioned Turnbo and Jackson, and asked them to step out of the truck, but they locked the van door. When police saw boxes labeled “Ruger” in the truck, they broke the van’s window, and the two suspects jumped out the other side of the vehicle and ran away.

Police seized stolen guns from inside this U-Haul van.

Police found Turnbo a few hours later and arrested him. Authorities have not yet found Jackson, and have offered a $5,000 reward for information leading to his arrest.

According to federal prosecutors, Turnbo admitted he was helping Jackson and his brother sell the stolen guns, but denied participating in the theft from the UPS facility. He allegedly admitted he knew Jackson had previously stolen guns from train shipments.