KNOXVILLE, Tenn. (WATE) – The FBI is offering a reward for a man they say robbed five banks in three states, three of which were in Tennessee, and carjacked a victim in West Knoxville just last week.

The man agents have dubbed the “Big Box Bandit” was first suspected of robbing the FSNB bank branch inside the Walmart in Clinton, Tennessee, in May. A few days later, the FBI says the same man robbed another FSNB branch inside a Walmart in Kingsport while carrying a manila envelope. In both robberies, they say he put the cash he obtained into the envelope.

“It’s escalating as far as we know,” said Special Agent Jason Pack with the FBI Knoxville Field Office. “Previously we’d only seen him use notes in an envelope that he carries and so most recently … he carjacked someone in West Knoxville, took that car from that person and used it in another bank robbery in Chattanooga – so we see that as an escalation.”

As agents began piecing together clues, they say they learned the same man robbed a bank inside a Walmart in Shelbyville, Indiana, and a standalone bank in Candler, North Carolina.

Officers now believe he also carjacked a person in West Knoxville on June 21 and used that vehicle in the robbery of a check cashing business inside another Walmart in Chattanooga.

“We do know he’s cased a few places he’s surveilled a few other banks that we are aware of,” said Pack. “So we know he hasn’t robbed those but he’s looked at a few others.”

The man has been seen driving a blue, older model Ford Taurus as well as the gold Chevrolet Trailblazer stolen in Knoxville.

Anyone with information is asked to call the FBI’s Knoxville Field Office at (865) 544-0751 or submit a tip online.