The three victims were walking together on The 606 on the 1800-block of North Monticello Avenue. At about 12:12 a.m., police said they were approached by three other people who asked them for their gang affiliations before shooting them.
"They also were asking the victims of their gang affiliations. They denied any," said Officer Jose Jara. "One of the offenders pulled out a weapon and started shooting."
A 22-year-old man was shot in the chest and back. He was pronounced dead at Norwegian-American Hospital, police said.
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He has been identified to the Cook County Medical Examiner's Office as Alejandro Aguado. Friends of the victim said he was killed when he stepped in front of the woman to protect her.
Aguado left behind a 2-year-old daughter, family said.
"His daughter will never again see her father," said Salvador Aguado, victim's father, through tears. "Never again see... never again see her dad."
A 19-year-old woman was shot in the stomach and transported to Mount Sinai Hospital in critical condition, police said. A 20-year-old man was shot in the lower back and transported to Stroger Hospital in stable condition.
Police said none of the victims are known to them. Surveillance video shows the apparent suspects fleeing the scene as Aguado lay dying. He worked two jobs to support his daughter.
"He had a lot of life," Salvador said. "It's very hard. Very, very hard."
No one is in custody.
Aguado, who lived in Calumet City, was apparently on the 606 because one of the friends he was with had just gotten off work nearby. Aguado's father believes it was his first time ever on that trail.
The 606 shooting was part of a string of shootings over a violent Memorial Day weekend, with 39 people shot, seven fatally.
In a public appearance Monday, Mayor Lori Lightfoot addressed the violence in her first week as mayor.
"It is quite amazing to see my email populated every few minutes it seems with reports of people being shot," Lightfoot said. "It's an unacceptable state of affairs."