A massive tsunami which resulted from the quake killed at least 11,417 lives, with 16,273 people still reported missing by police, three weeks on along with a massive nuclear crisis in Japan.
Recent radioactive iodine levels in seawater near the plant reached a new record - 4,385 times the legal limit. It was the highest reading since the quake which hit the plant on 11 March.
UN nuclear monitors have advised Japan to consider expanding the evacuation zone around the stricken reactors at the Fukushima Daiichi plant.
An exclusion zone with a radius of 20km (12 miles) is currently in place but the UN says safe radiation limits have been exceeded 40km away.