Over the last week, tribal violence has resumed in Nigeria's Plateau state. There, Moslems and Christian tribes battled over land use (Moslem herders versus Christian farmers.) This time there were about 1,100 casualties, including a hundred dead. Some 25,000 people fled the area, although 80 percent of those have since returned. Plateau state, in the center of the country, is where the largely Moslem north meets the largely Christian south. The tribal animosities are compounded by the religious and lifestyle (herder versus farmer) differences. The local and national governments have been unable to effectively deal with the disputes, which are becoming more violent as more people purchase cheap weapons. Since the 1990s, millions of Cold War surplus AK-47s and other weapons have been pouring into Africa, mainly from Eastern Europe. Tribal violence, which previously had been mostly shouting, shoving matches and brawls, are not deadly gun battles or one sided massacres.