A man and a woman were delivering packages in the 2100 block of North Lincoln Park West when an unknown vehicle pulled up next to them and two of the occupants jumped out.
The two people then pulled the man and woman from their vehicle and drove away with a 1-year-old girl and 5-year-old boy still in the backseat, police said.
The vehicle was later recovered in the 2000-block of North Stockton Drive with the children inside, less than a quarter mile away.
There were no injuries reported, police said. The entire incident played out steps from the Lincoln Park Zoo.
No one is in custody and Area Three detectives are investigating.