The Japan Meteorological Agency (JMA) issued a seismic alert this Friday for a supposed large earthquake of magnitude 9.9 in the Kuril Islands, but withdrew it eight minutes later, according to the Japanese Fuji News Network (FNN). The warning was disseminated at 12:40 local time and was canceled at 12:48. The alert affected several Japanese regions, including Hokkaido, Tohoku, Kanto, Hokuriku, and Tokai.
Subsequently, at 12:52, the JMA reported an earthquake that occurred around 12:38 near the Kamchatka Peninsula, with an estimated magnitude of 6.9 and an approximate depth of 160 kilometers. The agency indicated that the quake posed no tsunami risk and that no tremors of intensity 2 or higher had been observed at the points recorded in its information, according to FNN.
The JMA is investigating why the alert was issued with an estimated magnitude of 9.9. The information published by FNN states that the agency plans to explain the details in a press conference.
The agency acknowledges, in the general documentation about its early warning system, that magnitude estimates have limitations, especially in large earthquakes, and that false alarms can occur when using data from a single seismograph. However, there is no confirmed information that allows attributing Friday's incident to those factors.