On Wednesday morning, police charged Enrique Lopez, 25, with the slaying of 46-year-old Brinks courier Cresencio Borquez.
Borquez was shot and killed while loading cash into a drive-through ATM at a Chase Bank in Oak Cliff on Sept. 18.
Lopez and his brother-in-law, Jesus Sandoval, were arrested Saturday in connection with a Balch Springs bank robbery.
Investigators said Lopez confessed to the killing after he was arrested.
"We hope by bringing this individual to arrest, we can bring some solace for the family," Lt. Craig Miller said.
Two men were seen on surveillance video fleeing the Chase Bank in a white compact car after the slaying of Borquez.
The description of the car matches one of a vehicle used in a bank robbery in Balch Springs on Saturday, when two masked men stormed a Chase Bank on Lake June Road and threatened to kill the tellers.
Police arrested Lopez and Sandoval just minutes after police said they sped away from the bank.
Police said they are suspected in other North Texas bank robberies.
A relative of the men said Tuesday that they are "good people." The relative did not want to be identified.
"They did all that stuff without thinking of the consequences," he said.