New Delhi, July 2 -- As concerns grow over the likelihood of a devastating 'megaquake', the Japanese government has announced an update to its earthquake preparedness plan. The revision comes after new estimates warned of an increased risk of a powerful earthquake in the Nankai Trough.

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According to a government panel, there is now an 82 per cent chance of an earthquake with a magnitude of 7 or higher occurring in the Nankai Trough within the next 30 years. This marks a rise from the previous estimate of 75 per cent.

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Japan's Earthquake Research Committee ...