Magnitude 7.5 Earthquake Strikes Northern Japan, Tsunami Warning Issued

Apr 20, 2026

A magnitude 7.5 earthquake struck off the Sanriku Coast near Iwate prefecture in northern Japan on Monday at 4:53pm local time, prompting the Japan Meteorological Agency to issue tsunami warnings for waves up to 3 metres high. The tremor was felt across a wide area including Tokyo, hundreds of kilometres south, and triggered immediate evacuation orders for coastal and riverside communities. Prime Minister Sanae Takaichi established a crisis management team while officials worked to assess casualties and damage, with early NHK footage showing no immediate destruction at Iwate ports. The event occurs in a seismically active nation that experiences 1,500 earthquakes annually and suffered a devastating magnitude 9 earthquake and tsunami in 2011 that killed 18,500 people and triggered the Fukushima nuclear disaster.

Magnitude 7.5 earthquake and immediate tsunami warning

▪The magnitude 7.5 earthquake was felt across a wide area, shaking buildings in Tokyo, hundreds of kilometres to the south.
▪The Japan Meteorological Agency warned that the first tsunami waves could reach parts of the northern coastline immediately after the magnitude 7.5 earthquake.
▪The magnitude 7.5 earthquake hit in waters off Iwate prefecture on Japan's Pacific coast.
▪A magnitude 7.5 earthquake struck off northern Japan on Monday at 4:53pm local time (07:53 GMT).
▪The Japan Meteorological Agency issued a tsunami warning for waves of up to 3 metres (10 feet) following the magnitude 7.5 earthquake.

Government emergency response and evacuation orders

▪Prime Minister Sanae Takaichi said the Japanese government set up a crisis management team following the magnitude 7.5 earthquake.

Japan's earthquake vulnerability and historical context

▪Japan accounts for almost 18 percent of the world's seismic activity.
▪The Nankai Trough is an 800km (497-mile) undersea trench south of Japan where the Philippine Sea plate is sliding beneath the continental plate.
▪A magnitude 9 earthquake and tsunami struck northeastern Japan in 2011, killing about 18,500 people and triggering the Fukushima nuclear disaster.
▪The Japan Meteorological Agency issued rare megaquake advisories in 2024 and again in December last year after strong offshore tremors.

Perspective of Japan Meteorological Agency

▪The Japan Meteorological Agency warned that the first tsunami waves following the magnitude 7.5 earthquake could arrive immediately, leaving minimal time for evacuation.

Perspective of Prime Minister Sanae Takaichi and Japanese government

▪The Japanese government established a crisis management team to coordinate the emergency response to the magnitude 7.5 earthquake and tsunami threat.
▪Prime Minister Sanae Takaichi indicated that the Japanese government was still working to assess whether casualties or property damage had occurred following the magnitude 7.5 earthquake.

Perspective of Coastal residents and evacuees

▪Coastal residents in northern Japan were ordered to immediately evacuate to higher ground or designated evacuation buildings following the magnitude 7.5 earthquake.