Japan retracts mistaken magnitude 9.9 quake alert

TOKYO: The Japan Meteorological Agency (JMA) hastily retracted an erroneous alert for a magnitude 9.9 earthquake that it had issued minutes earlier, expressing regret for the disruption it caused. The alert had set off emergency notifications on millions of mobile phones on Friday, claiming a magnitude 9.9 quake had struck near the Kuril Islands, also known as Chishima Islands by Japan.

The JMA later corrected its information, revealing that the magnitude 6.9 quake had occurred near Russia's Kamchatka Peninsula just after noon. JMA spokesperson Shinya Tsukada apologized publicly for the "significant inconvenience and concern" the alert had caused. The alert's error originated from a mistake in calculating the earthquake's epicentre, which had been inaccurately estimated to be about 680 kilometres farther from Japan than it actually was, according to the JMA.

The agency attributed the error to a computational anomaly. Japan is still deeply affected by the devastating magnitude 9.0 undersea quake in 2011, which triggered a tsunami, causing around 18,500 deaths or disappearances and damaging the Fukushima nuclear plant. A magnitude 9.9 quake would have released approximately 22 times more energy than the 2011 event, according to local media reports.