 The quake occurred on the outer rise of the Kermadec-Tonga subduction zone.This is part of the Pacific Ring of Fire, where tectonic plates in the Earth's lithosphere meet and earthquakes and volcanic activity are common.Countries affected by the tsunami in the areas that were hit are American Samoa, Samoa and Tonga (Niuatoputapu) where more than 189 people were killed, especially children, most of them in Samoa.