Jon Whitley, a Charleston, South Carolina gun store owner accidentally shot and killed an employee after mistaking his personal handgun for a bb gun. The accident victim, Stefan Mrgan, age 36, died shortly after officers arrived at the gun store, Coastal Firearms.  “A witness told Deputies he saw the two men having a normal conversation, then he heard a firearm discharged. He said he saw Mrgan fall to the ground, bleeding.” 

There is an ongoing investigation.

Source:

“Charleston Gun Store Owner Accidentally Shoots, Kills Employee,” ABC News 4 (November 4, 2021).