Police said the shooting happened inside a JJ Fish and Chicken in the Wrightwood neighborhood near 79th and Western at about 10:30 p.m.
Police said the shooting happened after an argument between a customer and an employee, 42-year-old Mehdi Medellel.
Police said two customers started arguing with Medellel, and he, at some point, pulled out a handgun and fired shots. The two customers, a 55-year-old man and a 56-year-old man, were shot in their heads and died at the scene.
Another worker at the fast-food restaurant got word of what happened on Tuesday morning.
"I don't know why this happened or why he did what he did, what made him do what he do," she told ABC7.
She did not want to be identified and said she was not working at the time, but she knew one of the customers who was killed.
"He sat in there with me every day. Sometimes, I fed him. He was homeless. He didn't harm nobody or anything," the worker said.
JJ Fish and Chicken closed for business Tuesday afternoon. There were no visible signs left over from the deadly scene that played out less than 24 hours prior.
John Grant lives nearby and knows the area well.
"You know those peoples in there are really nice people, and their food is pretty decent, so I go there all the time," Grant said. "On this particular corner, you have to watch your back. You know, it's always something."
CPD said Medellel has been charged with two counts of first-degree murder. He is due in court on Wednesday.
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