RAPID CITY, S.D. (AP) — A South Dakota teenager accused in a fatal ax attack and other violent assaults will be tried in adult court, where he could face a significantly longer sentence.

The Rapid City Journal reports that 18-year-old Emery Arapahoe III was initially charged as a juvenile with second-degree murder and other charges. His case was moved to adult court during a hearing Monday.

Arapahoe, of Pine Ridge, is accused of attacking two people and killing a third during three separate incidents in 2017.

His attorney noted Monday that Arapahoe was 16 and 17 at the time. But Assistant U.S. Attorney Megan Poppen says the "nature of the charges" warrants moving the cases to adult court.

If convicted as an adult, Arapahoe could be sentenced to life in prison. Juvenile court allows defendants to be imprisoned until ages 21 or 26.

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