Claims that the recent magnitude 7.1 earthquake that struck southwestern Japan was man-made have been spreading online, with experts dismissing the theory as unrealistic in technological, financial and practical terms. Searches of posts mentioning an “artificial earthquake” in Japanese using an analysis tool from US firm Meltwater showed hundreds of references tracked in the days before the quake. They surged to about 10,000 on the day of the disaster and around 38,000 on the following day. While many posts reject the claims, assertions of a man-made origin to the disaster continue to be posted daily with tens of thousands of mentions. The Kumamoto earthquake struck at a depth of 16km (nine miles).