Japan’s Meteorological Agency apologises after mistakenly issuing a 9.9-magnitude earthquake alert, later confirming a 6.9-magnitude quake near Russia’s Kamchatka Peninsula.

Japan Withdraws False 9.9-Magnitude Earthquake Alert After Calculation Error

Erroneous Earthquake Alert Triggers Emergency Notifications Across Japan

By News Desk On Oct 17, 2026

TOKYO: (News Desk) – Japan’s weather agency has apologised after mistakenly issuing an alert for a massive 9.9-magnitude earthquake near the Kuril Islands before withdrawing the warning within minutes, briefly disrupting public transport and triggering emergency notifications on millions of mobile phones.

The Japan Meteorological Agency (JMA) initially reported on Friday that a magnitude 9.9 earthquake had struck near the Kuril Islands, also known in Japan as the Chishima Islands. The warning prompted loud emergency alerts across mobile devices, raising concerns about a potentially devastating disaster.

The agency later corrected its announcement, confirming that the actual earthquake measured 6.9 in magnitude and occurred near Russia’s Kamchatka Peninsula at a depth of around 160 kilometres (100 miles), shortly after midday.

“We deeply apologise for the significant inconvenience and concern caused to the public,” JMA official Shinya Tsukada told reporters.

Although the erroneous warning did not trigger widespread panic, it temporarily affected public transport services as authorities and commuters responded to the alert.

Calculation Error Behind False Warning

According to the JMA, the mistake resulted from an anomaly in the calculation of the earthquake’s epicentre.

The agency explained that the initial magnitude estimate was based on an incorrect assumption that the epicentre was approximately 680 kilometres farther from Japan than its actual location. This error led to the issuance of an exaggerated earthquake warning.

The incident has drawn attention to the importance of accuracy in Japan’s earthquake monitoring and early-warning systems, which are designed to alert residents quickly in one of the world’s most seismically active countries.

Japan’s Devastating Earthquake History

Japan remains deeply affected by the memory of the magnitude 9.0 undersea earthquake that struck in March 2011. The quake triggered a powerful tsunami that killed or left missing around 18,500 people and severely damaged the Fukushima nuclear power plant.

According to local media reports, an earthquake measuring 9.9 in magnitude would release approximately 22 times more energy than the 2011 disaster, highlighting why the initial alert caused concern despite being withdrawn within minutes.

The JMA’s apology followed the correction of the warning, with the agency acknowledging the disruption and anxiety caused by the erroneous announcement.