Keananna Streeter, 18, Fatally Stabbed Ex-Boyfriend's New Girlfriend, Police Allege

Police believe a Chicago teenager fatally stabbed her ex-boyfriend's new girlfriend because he wasn't helping her raise their baby.

Keananna Streeter, 18, was arrested Friday and charged with first-degree murder, according to the Chicago Sun-Times. She was ordered held Sunday on $500,000 bail in connection with the Sept. 1 stabbing that left a 32-year-old woman dead.

Police say Streeter confronted her ex-boyfriend in front of a convenience store on the West Side while his new girlfriend, Ragan McDougle, waited for him in an idling car, the Chicago Tribune reports.

"The defendant sprayed her ex with Mace and threw a bottle at the waiting car," Assistant Cook County State's Attorney William Hall told the Tribune. "The victim got out of the car in order to drive because her boyfriend could not. The defendant began fighting with the victim, stabbing her multiple times with a knife."

Witnesses saw Streeter and McDougle fighting and eventually broke the women up, driving McDougle to Mount Sinai hospital with stab wounds to her side, neck and temple, FOX Chicago reports. McDougle was pronounced dead the following morning.