Only one car was involved. It reportedly smashed into a utility pole about 3:40 a.m.
The Cook County Medical Examiner identifies the victims as 41-year-old Maricela Fuentes and 24-year-old Jose Martinez Fuentes of Chicago.
Two other victims remained in critical condition Sunday evening.
The crash occurred in the 1900 block of West Harrison, in front of Stroger Hospital.
Police say they expect to file charges against the driver.