Why the Lebanese forces have killed christians during the war?

i agree with 7mood. I think it was because Aoun declared war on the lebanese forces? i'm not sure about the details, but when aoun declared war to kick out the syrians, he was beaten badly, and ran away to france while his army got sluaghtered(what a traitor) , until the syrian army left lebanon in 2005. Then he comes back only when they pulled out of lebanon, and becomes their number 1 ally. I can not understand this man... just see aoun's speeches and the way he acts and you will understand why he declared war on fellow christians... anyway im not 100% sure if aoun did fight the lebanese forces, maybe someone can add to this?