By Vince Gerasole

(CBS) – Chicago police are investigating the possible sexual assault of a woman in a Loop alleyway.

The incident was reported to have occurred early Tuesday in the 200 block of West Van Buren.

A 50-year-old woman reportedly woke up in a daze and partially clothed and reported to authorities she was sexually assaulted in the alleyway.

Police were investigating the scene, CBS 2’s Vince Gerasole reports.

Vlesh Popi is the engineer for the building next door. Its cameras may have captured something.  But one of his employees he says did encounter a woman — she was dazed and naked from the west down — just before mid-day.

“She just wanted a cigarette from him, nothing else,” Popi says.

The woman was being treated at Mercy Hospital.

The area where the crime was reported is on the edge of the busy Financial District.

Concerned workers say this particular alley has been problematic.

“It’s always someone in the alley. They are smoking, they are drinking. People are always in the alley,” Diana Mitchell says.

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