A 21-year-old male victim was in the street in the 200 block of West Ontario Street in River North when someone wielding a knife forced him into a vehicle, police said.
While in the vehicle, the offender sexually assaulted the victim and then robbed him of personal property, Chicago police said.
The victim declined medical attention, police said.
No one was in custody. The offender's gender and description were not immediately available.
No further information was immediately available.
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