In a shooting caught on Facebook Live, a 20-year-old pregnant woman was wounded, while her 26-year-old boyfriend and her 2-year-old child, Lavontay White Jr., were killed.
The shootings highlight the street gang violence that police say was largely responsible for 762 homicides past year - almost 300 more than occurred in 2015 - and more than 3,500 shooting incidents.
Police said Lavontay White Jr. was shot in the head while sitting in the back of a vehicle.
Two-year-old Lavontay was pronounced dead at hospital along with his aunt's boyfriend.
The little boy who died, police say, is the nephew of a pregnant woman who was also shot.
Police said the pair were live-streaming their vehicle ride on Facebook Live as shots rang out.
Investigators were reviewing surveillance video from the area, and investigators had promising leads about the gunman, Johnson said. She runs into a house and yells, "They shot him ..." Two people forced their way inside, and then shot through the door of a 19-year-old man's room before taking off, police said. The woman is in critical condition. "Our children shouldn't have to keep paying the price for our inability to hold repeat gun offenders accountable for their actions". She and her unborn baby lived, but the boyfriend - a gang member, according to police - died at the scene.
Lavontay was the second child to die in Chicago on Tuesday as a result of a gunshot wound as the city continues to battle an uproar in gun violence. He did not have the names of the people who were shot and did not immediately know their relationship to each other.
Chicago has seen a spike in gang-related violence that has garnered national attention from both media and President Donald Trump. The city recorded more than 760 murders and 4,300 shooting victims previous year.
The violence has continued this year, with at least 76 homicides reported so far in 2017.
"We just can not afford to continue to see our children being shot down for things that they have no involvement in", Johnson said.