CNA Correspondent - The megaquake that never came: How Japan is preparing for the 'Big One'?

Japan is one of the most earthquake-prone countries in the world and it is preparing for what some are calling the “Big One”. For decades, an early warning system has been in place to give people precious time to seek safety. But critics argue it's actually making things more dangerous. Teresa Tang speaks to CNA's Michiyo Ishida to find out why.