According to police, the buyer used an online selling app called "Let Go" to arrange the deal.
Police say a 46-year-old man was waiting in his car in the parking lot of an apartment complex on Greens Parkway around 10 p.m. Tuesday.
He told investigators that a man wearing a mask walked up and pointed a rifle at him, so he pulled out his own gun and started shooting because he thought he was going to get robbed.
The suspect was shot and killed.
The buyer was a licensed concealed carry holder. The district attorney will decide on potential charges.
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