Police claim 19-year-old Quintonio LeGrier was "combative" ahead of the fatal shooting
An investigation is underway after police in Chicago shot dead a teenage college student and a mother of five.
They were shot when officers responded to a domestic disturbance call on the city's West Side.
Police admit that 55-year-old Bettie Jones was shot "accidentally".
In a statement, police said 19-year-old Quintonio LeGrier was "combative... resulting in the discharging of the officer’s weapon”.
They have not said if he was armed.
Mr Legrier's mother said her son had been dealing with mental health issues.
The two victims were black, but Chicago Police have not disclosed the race of the officer who fired the fatal shots.