The incident occurred at about 5:38 a.m. in the 4200-block of West Cullerton Street.
Police said a 15-year-old girl and a 25-year-old woman were attacked by a dog inside a home.
Officers arrived on the scene and shot the dog, police said.
The girl suffered multiple puncture wounds and lacerations on her arms and was transported to Stroger Hospital, where she was in serious condition, police said.
The woman suffered multiple puncture wounds and lacerations on her hands and was transported to Stroger Hospital, where she was in serious condition, police said.
Video showed animal control workers taking the animal away.
Further details were not immediately available.
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