William Young Jr., 59, said he confronted a man Tuesday at the Clackamas Fred Meyer store when he spotted the other man watching his wife punch in her personal identification number at the check-out terminal, The (Portland) Oregonian reported Thursday.
"I told him to get back but he kept staring," Young said. "I didn't know if he was planning to carjack us or what. Then we got into it."
The other man pulled out a handgun, which fired a round into Young's leg while the men struggled. Young continued to fight and other customers joined in to restrain the gunman.
Young was treated and released from a local hospital.
The suspect, Jerry Thomas Harryman, 66, was treated for minor injuries and arrested on a charge of first-degree assault. He was ordered held in lieu of $250,000 bail.
Police said Harryman had a permit to carry a concealed weapon, which was revoked at the time of his arrest.
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