Salopek was a general assignment reporter on the Tribune's Metropolitan staff, reporting on immigration, the environment and urban affairs. He spent several years as the Tribune's bureau chief in Johannesburg. Salopek reported from Sudan for a 2003 "National Geographic" story, "Shattered Sudan: Drilling for Oil, Hoping for Peace." He wrote "Who Rules the Forest?" from Africa for "National Geographic" in September 2005, examining the effects of war in Central Africa. While on freelance assignment for "National Geographic" in Darfur, Sudan, he was ambushed and imprisoned for more than a month in 2006 by pro-government military forces.