Police said the crime happened in the Belmont Cragin neighborhood. A man went into a building near North Lavergne Avenue and West Wrightwood Avenue and was able to enter a basement apartment.
A female person of an unknown age was sleeping in that apartment at the time, police said. The man battered her and tried to sexually assault her.
Police said the victim was able to fight the man off. That's when he fled the scene southbound on Lavergne Avenue.
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The offender is described as 20 to 30 years old, between 5-foot-8 and 6 feet tall and between 150 and 220 pounds. He was wearing all black, including black bottoms, a black hooded sweatshirt and black shoes.
Police asked anyone with information to contact Area Five detectives at 312-746-6554
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