Japan says tremors in North Korea were 10 times as powerful as previous nuclear test

TOKYO (Reuters) - Tremors caused by a suspected nuclear test in North Korea were at least ten times as powerful as the last time Pyongyang exploded an atomic bomb a year ago, the Japan Meteorological Agency (JMA) said on Sunday. "It was a least ten times as powerful," a JMA official said at a briefing aired by public broadcaster NHK. The previous nuclear blast in North Korea is estimated by experts to have been around 10 kilotons. (Reporting by Tim Kelly and Nobuhiro Kubo; Editing by Nick Macfie)