An earthquake measuring 7.5 on the Richter scale rocked northern Japan on Monday, according to the Japan Meteorological Agency (JMA), prompting a tsunami warning with the potential for waves reaching up to three meters high.

The seismic event occurred at 5:53 p.m. in the Pacific Ocean, just off the northern coast of Iwate Prefecture, with the tremors felt strongly enough to sway large buildings in Tokyo, located hundreds of kilometers away.

The JMA indicated that the earliest tsunami waves could make landfall on northern shores almost immediately after the quake.

Authorities urged residents to “Evacuate immediately from coastal regions and riverside areas to a safer place such as high ground or an evacuation building,” highlighting the anticipated risk of tsunami-related damage.

The agency also advised, “Tsunami waves are expected to hit repeatedly. Do not leave safe ground until the warning is lifted,” emphasizing the importance of remaining vigilant.

Despite the intensity of the quake, initial footage from national broadcaster NHK showed no visible signs of damage around several ports in the Iwate region.

PM’s office sets up crisis management team

The Japanese prime minister’s office said it had set up a crisis management team.

“For those of you who live in areas for which the warnings have been issued, please evacuate to higher, safer places such as higher ground,” Prime Minister Sanae Takaichi told reporters, adding that the government was trying to confirm whether there were any casualties or property damage.

Japan is one of the world’s most seismically active countries, sitting on top of four major tectonic plates along the western edge of the Pacific “Ring of Fire”.

The archipelago, home to around 125 million people, typically experiences around 1,500 jolts every year and accounts for about 18 percent of the world’s earthquakes.

The vast majority are mild, although the damage they cause varies according to their location and the depth below the Earth’s surface at which they strike.

Japan is haunted by the memory of a massive 9.0-magnitude undersea quake in 2011, which triggered a tsunami that killed around 18,500 people and caused a devastating meltdown at the Fukushima nuclear plant.

In 2024, the JMA issued its first special advisory of a possible “megaquake” along the Nankai Trough.

This 800-kilometre undersea trench is where the Philippine Sea oceanic tectonic plate is “subducting” — or slowly slipping — underneath the continental plate that Japan sits atop.

The government has said a quake in the Nankai Trough and subsequent tsunami could kill as many as 298,000 people and cause up to $2 trillion in damage.

The JMA lifted the 2024 advisory after a week but it led to panic-buying of staples like rice and prompted holidaymakers to cancel hotel reservations.

It issued a week-long second “megaquake” advisory in December 2025 after a magnitude-7.5 tremor struck off the northern coast.

The 8 December quake triggered tsunami waves of up to 70 centimetres and injured more than 40 people, but no major damage was reported.

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