56-year-olds Samuel and Barbara Lewis attempted to rob the MidFirst Bank located at 2225 N. May Avenue on Saturday morning. 

Police say the two were married, but aren't sure of their motive for robbing the bank.

The security guard approached the woman when she pulled out a handgun at a teller, then pointed it toward the security guard.  Tha'ts when the guard shot Ms. Lewis who ran out the front doors toward Mr. Lewis who was waiting in a car.

Mr. Lewis attempted to shoot the guard, but the guard returned fire.

Both Mr. and Ms. Lewis were left with multiple gunshot wounds and were transported to a local hospital.

Ms. Lewis died shortly after and Mr. Lewis is in stable condition.

Oklahoma has seen a rise in bank robberies so far this year.  We've already exceeded the average number of about 50 robberies per year, and it's only mid-July.

The Oklahoma Banker's Association said the state's doing all they can to prevent future robberies.

"Our rate of apprehension in Oklahoma are really good and the best thing about it is, we catch them before they go on and do ten more robberies or escalate to violence or whatever might happen," said Elaine Dodd, Vice President of the Fraud Division.

District Attorney, David Prater said that the security guard responded appropriately and that he probably saved the lives of customers and tellers who were inside the bank.