The police have been working hard in their efforts to solve the murder of Papuan activist Theys Hiyo Eluay, but the investigation has run into a brick wall. A military brick wall at that. This was the frank admission of Irian Jaya police chief Insp. Gen I. Made Mangku Pastika two weeks ago. The police have questioned 60 witnesses, and statements from eight of them point to the involvement of members of Task Force X Tribuana of the Army's Speci