Investigators say the man robbed the bank inside the Kroger store off of West Lamar Boulevard on Oct. 9 and a Capital One Bank in the 2200 block of North Collins Street on Oct. 14.
In each case, he walked up to the counter, demanded money and displayed a handgun, police said.
Police described the suspect as a black male, 25-35 years old, between 5-foot-6 to 5-foot-9, 160 pounds, with a goatee. In one robbery he was wearing a long sleeve khaki jacket with a black jacket with fuzzy lining, a black New York Yankees baseball cap with a metallic sticker on the bill and gold reflective sunglasses.
He is also a suspect in two other armed robbery cases from Crowley and Fort Worth, police said.
He may have fled in a blue sport-utility vehicle, possibly a Chevrolet or GMC, a white Dodge Avenger, or a red Hyundai sedan.
Anyone with information is asked to call Arlington police at 817-459-5678 or Tarrant County Crime Stoppers at 817-469-TIPS.