A magnitude 7.3 earthquake struck off the eastern coast of Japan near the Fukushima prefecture in the last hour, with authorities raising a tsunami advisory for possible waves of up to 1 metre and buildings swayed in the capital Tokyo.
The earthquake struck some 57 km east north-east of Namie, Japan at a depth of just over 60km, according to the USGS.
Parts of Miyagi and Fukushima prefectures are being warned of a potential 1 metre tsunami and a wide area of eastern Japan saw buildings shake, with skyscrapers rocked in the capital city.
Reports state that the shaking was felt for almost two minutes in some parts of eastern Japan, in the Sendai and northern Tokyo areas.
Power outages have been reported, but at this stage no reports of damage are emerging from Japan, partly due to the time of the earthquake which struck at around 11.30pm local time.
Approximately 2 million people are reported to be without power in Fukushima and Miyagi prefectures, with another 700,000 without power in Tokyo, utility owner TEPCO said.
Utility companies are checking nuclear power stations, which is a standard procedure now after any significant earthquake in Japan.
The magnitude 7.3 quake was preceded by one of M 6.4 in a very similar location. Both are not far from the location of the 2011 M 9.0 quake that drove the deadly tsunami and impacted the Fukushima nuclear power station.
As with any significant earthquake in Japan, there is a chance of a large number of insurance claims and potential impacts to reinsurance covers in the country.
Japanese earthquake risk is also a peril in the catastrophe bond market and at this time roughly $2.5 billion of cat bond risk capital outstanding has some exposure to Japanese quake loss events.
At this stage, it appears damage may be light, but given the quake struck at night a clear picture of damage and potential tsunami impacts may not be available for some hours. However, it seems unlikely this will be a major loss event at this stage, although a nasty reminder for residents of the tragic 2011 event just a few days after its anniversary.