Bujak died in a hospital five days after the accident, and police are still looking for the dog and its owner, who apparently untied the leash and left the scene, the Chicago Tribune reports.
The Cook County sheriff's department is looking for witnesses and asking for public help to find the dog's owner or additional information about the accident, according to the Journal & Topics.
The Cook County sheriff’s investigations unit can be reached at (708) 865-4896.
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