The incident happened in the 300-block of Cicero Avenue on Wednesday around 10:23 p.m.
A 27-year-old man was arguing with a man while riding a CTA bus.
During the argument, the man pulled out a sharp object, cut the 27-year-old and ran away with his stuff.
The victim was cut in the shoulder and was taken to the hospital. Chicago police said he was expected to be okay.
There is no one in custody. CPD Area Four detectives are investigating.
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