Firefighters in Pierce County say one person was found dead in a burning duplex in University Place. The Pierce County Medical Examiner's Office says 82-year-old Mary Ann Gough died of carbon monoxide poisoning and her manner of death was an accident. West Pierce Fire and Rescue says crews responded to a house at about 3:30 a.m. Monday and found smoke coming out of the back side of the duplex. They found one person dead inside. Two people who live in the other side of the duplex were not hurt; their unit was not damaged in the fire. The Pierce County Marshal's Office is investigating the cause.