The third nuclear incident to note happened at the Fukushima nuclear power plant in Japan.

The Tohoku earthquake, which occurred on Friday, March 11, 2011 on the east coast of northern Japan, is believed to be one of the largest earthquakes in recorded history, and the largest earthquake ever recorded in Japan. The earthquake and following tsunami resulted in over 19,000 deaths, inundated about 560 square kilometers, and caused $500 billion or more in damage and economic loss in Japan.

Fifteen nuclear power reactors at five sites were in the area affected by the earthquake and tsunami. Eleven of these reactors were operating at the time of the earthquake, ten of them at full power. All of the operating reactors shut down automatically in response to the seismic activity. The earthquake and following tsunami caused disruption to all fifteen reactors, ranging from partial loss of off-site power to complete loss of off-site and on-site power. The most severely affected plants were those at Fukushima Daiichi and Fukushima Daini.