Tulsa police say the Walgreens employee had a valid concealed-carry license.
Tulsa Police Sgt. Brandon Watkins says the 52-year-old customer pulled a gun and jumped over the photo counter to confront a clerk during the dispute.
Witnesses say the man grabbed photos from the clerk and then crawled back over the counter. While other employees called 911, a 28-year-old male employee fatally shot the customer. The man died Wednesday at a local hospital.
Police say the employee who shot the man was not arrested. Another Walgreens employee and a customer were struck by bullets and hospitalized. Both victims are expected to survive.
Police did not say whether the armed customer returned fire inside the store.
Walgreens issued a statement saying it's cooperating with the ongoing investigation into the shooting.
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