A woman suspected of shoplifting at a Walgreens on the Northwest Side was fatally shot after a manager confronted her and called for a friend who used to work security.

The man showed up with a gun at 11:30 p.m. Wednesday and started tussling with the 46-year-old woman, Chicago police said. After she fell to the ground, he shot her in the face.

He picked up the single shell casing and drove off from the store, located at 4817 W. Fullerton Ave., according to a police source. The woman had been carrying a t-shirt and five boxes of leggings.

Paramedics performed CPR while taking her to Mt. Sinai Hospital, where she was pronounced dead, police said. Her identity has not been released.

Detectives have identified the gunman, but he remained at large Thursday afternoon, police said. He was wearing a red hooded sweatshirt and dark jeans, and had driven off in a dark-colored SUV.

Store employees told police the shooting stemmed from a possible shoplifting incident, police spokesman Anthony Guglielmi said.

The store’s manager confronted the woman for shoplifting and tried to stop her at the door, a police source said. The manager called his friend who showed up minutes later and confronted the woman. While the former guard and woman were fighting, the man pulled out a gun and fired a single shot, which entered through her forehead, the police source said.

Unconfirmed radio reports initially indicated that the shooter may have identified himself as a police officer. But Guglielmi said the shooting “did not involve any law enforcement officer or agents.”

A police source said the suspected gunman, a 33-year-old man, has been arrested before on charges of impersonating a government official. The alleged gunman lives two blocks from the store and once worked for Monterrey Security, the Chicago Tribune reported.

County records show the 46-year-old woman has an arrest history including shoplifting.

A Walgreens spokesman wrote in a statement: “We are committed to providing a safe environment for our employees, patients and customers in the communities we serve.” The company referred questions about the shooting to police.

An autopsy released Thursday confirmed the woman died of a gunshot wound to her face, the Cook County medical examiner’s office said. Area North detectives are conducting a homicide investigation.

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