Clinton J. Johnson U.S. Attorney | U.S. Attorney for the Northern District of Oklahoma
Mark Verron Callshim, Jr., 38, of Tulsa, has been sentenced to over 15 years in federal prison for his role in a 2021 armed robbery at a Tulsa convenience store. U.S. District Judge Sara E. Hill imposed a sentence of 184 months for Robbery in Indian Country and Carrying, Using, and Brandishing a Firearm During and in Relation to a Crime of Violence. Callshim will also serve five years of supervised release after his imprisonment. The federal sentence is set to run consecutively with his existing 20-year state sentence for aggravated assault and battery.
A federal jury convicted Callshim in September 2025 after reviewing evidence that included surveillance footage from the robbery. The video showed two men arriving at the store in a blue vehicle; one man, identified as Callshim by his distinctive tattoos and clothing, was seen brandishing a firearm alongside another suspect. Both suspects threatened the cashier with guns before taking cash from the register. As they left, the second man fired a shot at the building.
Tulsa Police responded quickly to the scene and established a perimeter based on descriptions from surveillance footage. A citizen later reported seeing someone abandon the blue vehicle about a mile away from the store. Officers determined that the car had been stolen days earlier, and with permission from its owner, searched it for evidence. They recovered several items including a partially smoked cigarette, which was submitted for DNA analysis.
An internal tip within the Tulsa Police Department led detectives to Callshim, whose identity was confirmed through tattoos, shoes, and DNA evidence found in the stolen car. Court records indicate that Callshim has previous convictions for assault with a dangerous weapon, drug possession, fleeing law enforcement, and first-degree robbery.
The second suspect involved remains unidentified. Authorities are asking anyone with information to contact the FBI at tips.fbi.gov/home or by calling 405-290-7770. Anonymous tips can also be submitted to Tulsa Crime Stoppers by phone at 918-596-2677 or through their website.
Callshim is identified as a citizen of the Ponca Tribe of Indians of Oklahoma and will remain in custody until he is transferred to federal prison facilities. The case was investigated by both the FBI and Tulsa Police Department; prosecution was handled by Assistant U.S. Attorneys Mike Flesher and John Brasher.
