Aug 21 1986
1,700 people are killed in Cameroon when Lake Nyos emits a huge cloud of fast-moving fog, quickly enveloping the villages of Nyos, Kam, Cha, and Subum. The lethal mist, consisting mainly of carbon dioxide and water vapor, displaces the oxygen in the low-lying zones, killing thousands of cattle and even more birds and wild animals. One eyewitness later describes the landscape as being "littered with human remains and animal carcasses."