FORT WORTH (CBSDFW.COM) — Fort Worth police are investigating a shooting at a auto parts store Sunday morning.

So far, police have only said that a customer was being belligerent to a clerk at the AutoZone store in the 8600 block of South Hulen Street.

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According to officials, the customer started patting himself as if he had a weapon.

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It was at that point that police say the employee shot the unidentified customer– who at last check was in critical condition.

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Investigators say the clerk, who also has not been identified, is cooperating with officers. Staff