Massive 7.5 magnitude earthquake rocks Japan sparking evacuations and tsunami warnings

Japan Meteorological Agency confirmed a premlinary magnitude of 7.9, hitting a depth of 10km in water around 100km off the Sanriku coast.

The agency issued a tsunami warning and confirmed it expected staggering waves of up to three metres (9.84 feet) to engulf large coastal areas across northern Japan.

So far, some 3,650 people from 2,024 households have been ordered to leave their homes in Niikappu, Hokkaido.

With a tsunami being detected 60km off the coast of Iwate, people have been instructed to "evacuate immediately" and to brace for a tsunami.

The coast of Aomori is the third northern coast to receive a tsunami warning with the impact hitting 30 minutes after the quake was detected.

The central Pacific Hokkaido coast, the Iwate prefecture coast and the Aomori prefecture coast are all expected to be the worst-hit areas.

The Prime Minister Sanae Takaichi confirmed her Government had established an emergency task force and encouraged citizens in the affected areas to get to safety.

Ships could be spotted sailing out of the Hachinohe port off Hokkaido's coast ahead of the oncoming waves, national broadcaster NHK said.

Alerts of "Tsunami! Evacuate!" blinked across the screen, they added.

Meanwhile, on land, bullet trains ferrying passengers from Tokyo to Aomori have been halted after the quake, media outlet Kyodo said.

There are no nuclear power plants currently in operation across the Hokkaido and Tohoku regions.

However, Hokkaido Electric Power Co and Tohoku Electric Power Co have several nuclear power plants across the region.

Tohoku Electric said it was checking the impact of the mammoth quake on the Onagawa nuclear plant.

Japan's location in the Pacific Ring of Fire - a region which records approximately 90 per cent of the world's earthquakes - means the nation is prepared for major tremors such as the one today.

It is estimated the country records up to 100,000 total seismic events per year but only feels up to 2,000 of them.

Usually, major earthquakes above a magnitude seven are recorded in Japan just once a year.

However, this morning's warning to Japanese citizens has come just four months after a major magnitude 7.6 earthquake struck in roughly the same region off the northeast coast of Japan.

The December quake left at least 13 people injured and triggered a warning for Britons from the Foreign Office.

Although today's tremor generated a three-metre tsunami warning, it falls well short of the 13-metre wave generated by the magnitude-9 Fukushima earthquake which devastated Japan in 2011.

The peak of that wave is reported to have reached 40 metres.