Police have not said if the carjackings are connected.
Officers responded to the 3200-block of North Ashland Avenue at about 2:20 a.m. and found an 18-year-old victim.
The victim told police two male suspects got out of a black Jeep and approached him as he was entering his vehicle.
One of the suspects pointed a gun at the victim and demanded the keys to the vehicle, police said. The victim complied and the suspects fled in the black Jeep and the victim's black Honda Civic.
A second carjacking was reported in the 4000-block of North Ashland Avenue at about 3:43 a.m., police said.
Two victims told police that three male suspects got out of a black sedan and approached them as they were parking. A suspect pointed a gun at the victims and demanded the keys to the car, police said.
The suspects then fled in a red Dodge Charger with the black sedan trailing behind, police said.
No injuries were reported and no one is in custody in either carjacking. Area Three detectives are investigating.
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