An earthquake caused the disaster

In 1997, scientists from the United Institute of the Physics of the Earth concluded that a seismic event occurred near Chernobyl beginning approximately 16 seconds before the explosion that initiated the disaster. If vibrations from an earthquake disrupted the reactor's control systems, that could have triggered the cascade of events that led to the catastrophe. Adding further intrigue to the earthquake theory, both the Soviet Union and their Cold War enemy the United States had worked on the development of tectonic weapons - weapons potentially used to cause seismic events by manipulating geological features of the Earth's tectonic plates - prior to the Chernobyl disaster. The former Soviet official newspaper Pravda reported in 1992 that a tectonic weapon had been developed by the Soviet Union, and given the limited seismic activity of the region surrounding Chernobyl, the possibility that such a weapon was employed there must be considered.