Police said the carjacking happened in the LeClaire Courts neighborhood's 4400 block of South Lawler Avenue at about 11:20 a.m.
A teen boy was inside a stopped vehicle when three armed people approached him, police said. One of the offenders demanded the victim's vehicle, and he complied.
Police said the armed group then got into the teen's vehicle and fled the scene in an unknown direction.
No injuries were reported. No one is in custody and area detectives are investigating.
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