(Portland, OR)  --  Police say they've arrested a man accused of killing another man in northwest Multnomah County.  Sheriff's deputies responded to a home in the 18-hundred block of Northwest 6th Avenue early yesterday morning on reports of a disturbance involving a weapon.  Responding officers found a 44-year-old man suffering from serious injuries to the neck.  Police tried to save the man's life, but he died at the scene.  Police arrested a 42-year-old man at the scene for his death.