It was unclear whether the person killed, 17-year-old Jarrod Reed of Muskogee, was among several people involved in the shooting or a bystander, he said. Details about the other victims, including their conditions, haven't been released, hospital spokesman Chad Wetz said.
Three people were being sought for questioning late Saturday, police said.
Shoppers were told to leave quickly by a public-address announcement around 4:15 p.m., and they gathered outside. Several said they'd heard four or five shots inside the mall.
Tonya Pierce said her daughter and two friends were waiting for a ride home when shots rang out. Her daughter told her that "people started screaming" and a group of men started shooting, Pierce said.
Witnesses told police they thought it was a gunfight, Zardeneta said. Gunfire was reported but not confirmed elsewhere in the city after the mall shooting, he said.
Screams grew to a crescendo as shoppers fled the shopping center, said Hope Bridges, manager of Kat Daddy's Bar and Grill in the mall. She called 911 and was told to evacuate her nearly full restaurant.
Merchants had looked forward to Saturday's festival drawing more business, she said.
"It was a great business day for the mall. Everyone was happy, everybody was in town," Bridges said. "It was something the mall had been looking forward to."