SIOUX FALLS, S.D. (KELO) — A man from the Pine Ridge Reservation is headed to prison for a 2016 murder.

A federal judge sentenced Stetson Eagle Elk to 18 years behind bars. He previously pleaded guilty to second-degree murder and aiding and abetting. Other charges were dropped.

Court papers say in August of 2016, Eagle Elk, Gary Little Bull and the victim, Todd Little Bull, came up with a plan to kill Todd as part of a spiritual act. They were planning to blame the death on another spiritual leader.