The families of two black Chicagoans killed by police on Sunday accused officers of having used excessive force and Mayor Rahm Emanuel of having failed them, piling pressure on a city facing a U.S. federal probe over possible racial bias in policing.

Police, responding to a domestic disturbance call, shot Quintonio LeGrier, 19, a male college student who was visiting his father, and Bettie Jones, a 55-year-old mother of five, on Saturday.

Family members said police were called after LeGrier threatened his father with a metal baseball bat. Jones, who lived in a first-floor apartment, was shot through the door, according to her cousin, Evelyn Glover.