The earthquake of August 13, 1868 struck near the city with an estimated magnitude of 8.0 to 9.0 Estimates on the death toll vary greatly, some estimates have the number at 25,000 to 70,000 people. Others estimate that the population of Arica was less than 3,000 people and the death toll was around 300. It triggered a tsunami, measurable across the Pacific in Hawaii, Japan and New Zealand. As Arica lies very close to the subduction zone known as the Peru–Chile Trench where the Nazca Plate dives beneath the South American Plate, the city is subject to megathrust earthquakes.