The crime happened at about 6:30 a.m. in the 5100-block of South Rutherford Avenue in the city's Garfield Ridge neighborhood.
A woman, 41 was walking to her car when a female suspect stabbed her and stole her Nissan Rogue, police said.
Neighbors told ABC7 the victim is a teacher, and she had just started her car to warm it up when the attack happened.
The 41-year-old was stabbed in the chest and bicep; she was taken to the hospital in critical condition.
The victim ran across the street for help and rang her neighbor's doorbell.
The neighbor did not want to be on camera, but told ABC7 her doorbell camera captured most of the three-minute long attack.
"She rings the doorbell, and she just says, 'call the police I'm getting robbed.' Then, she goes to my next-door neighbor, and, on the camera, you can hear her screaming. She's getting stabbed," the neighbor said.
Minutes after driving off in the Nissan, the suspect crashed into a parked car a few blocks over, in the 5100-block of South Mulligan Avenue.
A 30-year-old man heard the crash, and approached the SUV to try to help, but the suspect stabbed him, too.
He was stabbed in the back. He was taken to the hospital and is expected to be OK.
Witnesses said he was a father taking his 2-year-old to daycare.
"She jumped out of the car, and went after him. I think she was also trying to take his vehicle, while he was trying to put his kid in the car and be on his way to work," a witness said.
The man and a neighbor who called 911 detained the attacker until police could get there.
The man's child was unharmed.
The female suspect was placed into custody at the scene and was taken to the hospital with minor injuries from the crash.
The neighborhood is on edge.
"She's a Chicago Public Schools teacher. She wasn't trying to hurt anybody. She was just warming her car up, getting ready for work. I'm just happy I was there for her," James Carr said.
Carr said he's no hero for coming to the aid of one of his neighbors.
He said he was awakened by banging and screaming.
"I ran to the front door, and the lady was being stabbed. So, I immediately opened the door, and confronted the person, pulled the lady inside the house," Carr said.
The investigation is ongoing, and charges are pending.
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