The government was urged to amend a special law enacted in 2004 to prepare the public for a megaquake in either the Japan Trench that is part of the Pacific Rim of Fire off northeastern Japan or the Chishima trench that lies off Tokachi in Hokkaido and stretches to the Kuril Islands.
The 7.4 magnitude quake that hit Tohoku shook a region that’s still recovering from the devastation of the March 2011 disaster. Experts are split on whether the quakes are closely linked.