The shooting was contained to the Firebirds Wood Fired Grill restaurant in the La Encantada mall in Tucson, said Pima County Sheriff's Department spokesman Cody Gress.
When Pima County sheriff's deputies arrived, they found two men dead from apparent shotgun wounds and a woman who was injured with an apparent gunshot wound.
Gress said that the woman was shot in the leg and her injuries are not life-threatening.
According to the sheriff's department, deputies believe that the three people involved knew each other and only one gun was used. Authorities said that the shooting was not random, did not involve any other areas of the mall and did not result in any bystanders being hurt.
Gress said there were "quite a few people" in the restaurant at the time of the incident. He did not have information about the relationship between the people who were shot.