TOKYO: Japan's weather agency withdrew an erroneous alert for a magnitude 9.9 earthquake minutes after issuing it, apologising for a warning that disrupted transport.
The Japan Meteorological Agency (JMA) had initially warned on Friday that a magnitude 9.9 earthquake had occurred near the Kuril Islands, known in Japan as the Chishima Islands, triggering loud emergency alerts on millions of mobile phones.
The JMA later clarified that a magnitude 6.9 quake had occurred near Russia's Kamchatka Peninsula at a depth of 160km just after midday.
"We deeply apologise for the significant inconvenience and concern caused to the public," JMA official Shinya Tsukada told reporters.
The alert did not cause widespread panic but briefly disrupted public transport.
According to the JMA, the error stemmed from an anomaly in calculating the earthquake's epicentre.
The estimated magnitude was based on an incorrect assumption that the epicentre was about 680 kilometres farther from Japan than it actually was, the weather agency said.
Japan is haunted by the memory of a massive magnitude 9.0 undersea quake in 2011, which triggered a tsunami that killed or left missing around 18,500 people and wrecked the Fukushima nuclear plant.
A magnitude 9.9 tremor would have released about 22 times as much energy as the 2011 quake, according to local media.
© New Straits Times Press (M) Bhd