Police said it happened in the Loop's 0-100 block of East Monroe Street in front of the Palmer House Hilton Hotel around 6 a.m.
A 58-year-old man got out of his car to get things out of his trunk, police said. That's when two unknown people approached, got into the driver's and passenger's seats and drove off.
No injuries were reported.
No one is in custody, and Area Three detectives are investigating.
Police did not immediately provide further information.
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