ATLANTA (CBS46) -- A cashier asked a customer to put on a mask, but instead, witnesses say the man shot the worker in her head.
The GBI has taken over the investigation of the deadly shooting inside DeKalb's Big Bear Supermarket.
"[He] raised his arm and two fires, two gunshots. I turned around, left my basket and went running to the back," Glenda told CBS46. The shopper was one of the many who took cover around one o'clock Monday afternoon.
"Then I still heard more firing and I said, 'oh Lord he's going to kill everybody in the store," she continued.
The supermarket shooter, Victor Tucker, is accused of killing one woman and injuring two others including an off-duty deputy for DeKalb County Sheriff's Office. The deputy was working a security shift for the store.
"When I heard the first shot, I got down behind the protective barriers," said George Scott.
He explained the chaos inside the packed store. Some witnesses even told CBS46, older customers struggled to run because of their disabilities.
Investigators confirm Tucker argued with a cashier about his mask. He left the store with nothing then came back with a handgun. After firing and ultimately killing the worker, the 30-year-old turned his weapon the deputy who tried to intervene.
Both the suspect and the officer were wounded during the shootout. The GBI says a bullet also grazed another employee.
Allen Williams recalled standing next to the woman, in fear for his own life.
"Had I not turned, the graze would have went from her and hit me." Williams added, "I was just blessed to get out of there."
The DeKalb County Sheriff's Office said in an afternoon press conference if it were not for their veteran officer working security at the store full of shoppers, the outcome likely could have been much different.
"He is a 30-year veteran and he has truly served his time." Sheriff Melody Maddox says, "we just want to make sure, and let everybody know that we are most of all, pleased he is okay."
The officer was wearing a bullet proof vest.
CBS46 is working to confirm the identity of the officer and the fatal shooting victim.
The officer and suspect remain in the hospital.