CHICAGO (CBS) — A man suspected in the shooting death of a Walgreens shoplifting suspect has turned himself in to police and is being questioned.

Before he turned himself in, several family members arrived at the Area South Police Station.

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Sources say the man shot and killed a suspected shoplifter inside a Walgreens in the Belmont Cragin neighborhood last week.

Sources tell CBS 2 the store clerk spotted Sircie Varnado shoplifting, and instead of calling 911 called a friend. The friend allegedly showed up with a gun, falsely identified himself as an officer, then words turned into fists.

He ultimately pulled the trigger, killing Varnado, a 56-year-old mother of five.

“She didn’t deserve to be executed like that. He could have just held her for the police. He didn’t have to shoot her in her face. She didn’t have no weapon,” said Varnado’s sister April Reed.

The man being questioned in connection with the Walgreens shooting was arrested last summer, accused of threatening a woman and once again claiming to be a cop.

Charlie De Mar