The witness rushed out of the bathroom and notified staff at the Publix Supermarket. When police arrived soon after, they arrested a suspect as he was exiting the bathroom -- with six loaded guns in his possession.
The suspect, identified as 22-year-old Rico Marley, now faces a slew of charges related to the incident, which came just days after 10 people were killed in a mass shooting at a supermarket in Boulder, Colorado.
It was that tragedy that was fresh in the mind of the Instacart shopper, Charles Russell, he told CNN affiliate WSB.
"I saw an AR-15," he said. "And I was like, you know, this kind of startled me just again with events that recently happened in the grocery store up in Colorado."
Authorities have not said what they believed Marley intended to do with the weapons.
According to the police incident report, Russell was entering the men's restroom when he "heard clicking sounds from the bathroom stall."
"It sounded to him like someone was loading firearms," an Atlanta officer wrote. "He also told me that he saw an AR-15 style rifle leaned against the wall."
By the time the officer arrived at Atlantic Station -- a commercial and residential complex in Atlanta just north of downtown -- the supermarket appeared to have been evacuated, the report says.
The officer wrote that he donned a ballistic helmet and took his city-issued rifle into the store, where he immediately saw the suspect coming around the corner from the restroom, just feet away. The officer ordered the suspect to put his hands up and not move, the incident report says.
"The accused appeared to be surprised when he saw us that close to him," the officer wrote. Marley was detained without incident, the report says.
Suspect denied bond
After arresting Marley, police recovered six firearms: a DPMS AR-15-style rifle, a 12-gauge Maverick Arms Modell 88 shotgun, three semi-automatic 9 mm pistols and a .38-caliber revolver. All of the weapons were loaded and the rifle, shotgun and three 9 mm pistols all had a round in the chamber, according to the police report.
The suspect, who was wearing body armor when he was arrested, had the four handguns in his clothing while the rifle and shotgun were being carried inside a bag, the report says.
Marley has been charged with six counts of possession of a firearm or knife during commission of or attempt to commit certain felonies and five counts of criminal attempt to commit a felony.
Marley, who's being represented by a Fulton County public defender, waived his first court appearance Thursday, where Judge Rashida Oliver ordered him to be held without bond due to the "danger risk to the community at large." He's being held in the Fulton County Jail.
The Fulton County Public Defender's Office did not respond to CNN's request for comment Thursday.
In a statement, a spokesperson for Publix said the company was cooperating with investigators and that "the safety of our associates and our customers is our priority."
"We are thankful that there were no injuries, and all were able to exit the store safely."
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