Authorities did not release any information on the teen, including hometown or relationship to the soldiers.
Authorities said a dispute may be behind the abduction of Harris in his truck by Mellish, who then allegedly drove more than 300 miles to his hometown of Brooklyn. The two soldiers and the juvenile then traveled to Ross Road in Byram, where investigators believe Harris was killed.
Byram Township police found Harris body, nearly buried under snow, about 200 feet into the woods off the cul-de-sac. Firefighters called police to the scene after they found blood and several scattered items while on their annual Santa ride through the township.