CHICAGO (CBS) — Two and a half months after a shooting at an Aurora warehouse left five people dead, a Dolton man was arrested for threatening to pull a handgun on a coworker at another Aurora warehouse, police said.

David Cox, a temporary employee at Glanbia Performance Nutrition at 600 Commerce Ave., was arrested at work after Aurora police found a loaded gun and additional loaded magazines and additional rounds in his work locker.

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He does not have a valid FOID card.

(Credit: Aurora Police Department)

Police say earlier in the week, Cox told a coworker he was going to “pull a pistol” on them. Later that day, another employee noticed Cox wearing a fanny pack, which he believed contained a weapon. The employees eventually notified management, who immediately called police.

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A search of Cox’s locker revealed the fanny pack with a 9 mm Smith and Wesson handgun loaded with 14 rounds and two additional loaded magazines with 27 additional rounds.

Cox has been charged with with misdemeanors for unlawful use of a weapon and possession of a firearm without a FOID card. It is unknown if these charges will later be changed to felonies.

Cox will appear in court in DuPage County at a later date.

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On Feb. 15, Gary Martin opened fire inside the Henry Pratt Company warehouse in Aurora after he was told he was being fired for a safety violation. He killed five fellow employees, and wounded one other. He also shot and wounded five police officers who responded to the shooting before he was killed in a shootout with police.