A source close to the investigation said the call came into 911 from a family member, who said the children's mother "snapped" and stabbed the children before starting the fire.

Four people, including two children, were hospitalized after a stabbing and reports of a fire on the city's Northwest Side on Friday morning, a source told ABC7.

A woman is in custody after three children were found stabbed inside a burning building in Chicago's Logan Square neighborhood, according to police.