By Charlie De Mar

CHICAGO (CBS) — Orland Park police are investigating an apparent murder-suicide outside a P.F. Chang’s restaurant on Sunday.

Around 5:20 p.m., officers responded to a report of shots fired in the parking lot outside a P.F. Chang’s at 142nd and LaGrange Road in Orland Park.

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“We were having dinner, and we walked outside, and as soon as we walked outside, we heard about six gunshots,” one witness said.

Orland Park Police Deputy Chief Joe Mitchell said a preliminary investigation showed the shooting was a murder-suicide.

Authorities said 43-year-old Renee Isadore, of the Mount Greenwood neighborhood in Chicago, was found dead inside a vehicle in the parking lot, and 59-year-old Steven Shereyk, of Willow Springs, was found dead on the ground next to the vehicle.

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Police said Isadore had been shot multiple times, apparently by Shereyk, who had suffered a self-inflicted gunshot wound.

Investigators said the two had a relationship, but were not married. As police were conducting their investigation, a man rushed the crime scene, yelling, “That’s my wife!”

Ivory Crosby said she saw the two talking calmly moments before the shooting.

“Just seen them standing there, like they were trying to decide to go in,” she said.

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Autopsies were scheduled for Monday.

Charlie De Mar