ELKHART, Ind. (AP):  Northern Indiana police say a 12-year-old girl fatally stabbed her stepmother after the woman confronted her about starting a fire in the family's apartment.

Elkhart Police spokesman Sgt. Chris Snyder says officers arrested the girl without incident Friday after finding her walking along railroad tracks in nearby Bristol.

Snyder tells the South Bend Tribune (http://bit.ly/1CX0LAO ) the girl is being held at Elkhart County's juvenile detention center, pending an initial hearing that's expected within a few days.

She hasn't been formally charged.

Police say the girl and her stepmother argued Thursday night, prompting the girl to start a fire in her own bedroom.

When the woman confronted her stepdaughter about starting the fire, police say the girl stabbed her. The woman died before emergency responders could take her to a hospital.