Japan has issued a warning about an increased risk of a major earthquake, but officials stress it's not imminent. The advisory comes after a 7.1 magnitude quake struck off the southern island of Kyushu, which caused no major damage. Experts are concerned because the epicentre was near the Nankai Trough, where megaquakes have left thousands dead in the past. There's a 70-80% chance of a magnitude 8 or 9 quake striking within 30 years, potentially causing over 200,000 deaths.

Source: https://www.bbc.com/news/articles/c9qgv8pg59ro