The Jackson County coroner tells media outlets each boy had a gunshot wound to the head. It's unclear whether the first shooting was an accident.
Jackson City Police identified the boys as Austin Wiseman and 9-year-old Blake Campbell. Investigators say they lived together at the home, where the shootings occurred Wednesday in an upstairs bedroom.
Police investigating the case don't believe anyone else was directly involved in the shootings. Authorities have said no one else was at home at the time and that a .44-caliber handgun was recovered.
Jackson is a city of about 7,000 people in mostly rural Appalachian Ohio, about 65 miles south of Columbus.
