Thousands of people have spent the night in emergency shelters in Japan after a powerful earthquake hit the west Coast of the main island. Four people have died, but many more are thought to be trapped beneath the rubble of collapsed buildings. The epicenter of the 7.6 magnitude quake was in the province of Nato. With tremors felt hundreds of miles away in the capital, Tokyo, tens of thousands of people were told to head to higher ground. So Ranjana Tewari has the very latest from Japan.

This footage from inside someone's home captures the moment the powerful earthquake struck. Some staff at this news network took cover, while others wanted to cover the story. The 7.6 magnitude earthquake struck just after 4:00 in the afternoon local time. It was caught on camera in this supermarket. There was chaos and confusion. Tunami warnings were issued then downgraded on the Ishikawa coastline, and people were told to head to higher ground.

I would like to ask all residents to continue to pay close attention to the occurrence of this strong earthquake. If you are in a region where a tsunami is expected, please evacuate as soon as possible.

More than 140 kilometers from the epicenter, this video was taken by English teacher, Barney Davis.

It just kept going. It was really long. And the fridge door was opening and shutting. Pictures were going all over the place. Everything fell off the shelves. It was pretty traumatic.

Barney and his family went to the local evacuation center until he was told it was safe to return home. But then...

Literally, just as we're talking, my phone's given us an alert there's been another little earthquake up north again. The whole evening has been aftershocks.

Despite the damage to roads and buildings, this earthquake is not as severe as 2011, when a magnitude nine quake triggered a tsunami, leading to a nuclear meltdown at the Fukushima power plant. This time, all nuclear facilities are currently unaffected. But following the earthquake, a huge fire broke out in one of the affected areas, and thousands are now spending the night outside and below zero temperatures, fearful of going back into their homes as aftershocks continue to hit.

So, Nezhatna, it's a daybreak now where you are. What's the latest?

That's right, Clive. Authorities have now downgraded that major tsunami warning that was issued in Ishiwaka, Perfecture, when the earthquake struck. Dozens of aftershocks did trigger waves of about 1 meter, which was felt across the west Coast of Japan and as far as South Korea. What we know is that houses have been damaged, that some fires have started, and that army personnel have been deployed to try and help with the response. There are already reports that infrastructure has been damaged and officials have warned that there may be more shocks, after shocks and tremors in the coming days. Now, as you mentioned, almost 100,000 people spent the night in evacuation centers. Tens of thousands of homes don't have power. Even here where I am in the mountains, neighboring Nagano, Perfecto, we felt the tremors and also it's near freezing temperatures here, so it's a real problem if there are power cuts. Japan's vast transport network has also been affected by those power cuts. But Clive, because Japan is such a hotbed of seismic activity, the government has a pretty great and sophisticated warning system, a tsunami and earthquake warning system. We all got signals on our mobile phones ahead of the earthquake, and so people were able to go and get shelter.

As you said, Daybreak now, so we'll know more about what the real damage is to buildings, roads, infrastructure, and how many people are trapped as well.