UPDATED 02/10/12 11:23 a.m.

CHICAGO (CBS) — A 54-year-old woman was just trying to do her job at a Humboldt Park Subway sandwich shop, when a man with a gun came in and shot her.

Now that woman has died.

As CBS 2’s Susanna Song reports, the unidentified woman had been in critical condition at Stroger Hospital of Cook County all night after being shot at the Subway at 1129 N. Western Ave. The Subway is located just across Haddon Avenue from Roberto Clemente Community Academy.

She was trying to escape through a back door when the robber shot her in the neck.

The restaurant’s former owner, Bieu Hoang, said he had hired the woman who was killed. The 54-year-old woman lived in the Uptown neighborhood.

“She worked very good, no complaints,” Hoang told CBS 2’s Mai Martinez.

The Subway is usually open at 7 a.m., but it was shuttered Friday morning. A sign on the front door said it was “temporarily closed.”

Around 9 p.m. Thursday, an armed man walked into the Subway and shouted he was robbing the restaurant. After shooting the woman, he demanded that another worker open the register.

The robber took an undisclosed amount of cash and ran away. The second worker apparently was not hurt.

There is an infrared camera in the parking lot of the Subway, but there is no word on whether the man was captured on the camera, or if police have been able to use surveillance video to help them in their search.

Police have not released a description of the suspect.

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