ISHINOMAKI, Japan (AFP) - People all over Japan bowed their heads in silence Monday as they remembered the almost 19,000 who died when a ferocious tsunami surged ashore two years earlier.

Ceremonies were held in towns and cities throughout the disaster zone, as well as in Tokyo, where Emperor Akihito and Empress Michiko led tributes to those who lost their lives in a disaster that also sparked a nuclear emergency.

As a mournful quiet descended, cold winds blew through the grounds of Okawa Elementary School, in Ishinomaki, where at least 70 children were swept to their deaths by the rising waters on March 11, 2011.

The city’s tsunami alarms were sounded at 2:46pm (0546 GMT), marking the exact moment a 9.0-magnitude undersea quake hit, sending a massive tsunami barreling into Japan’s northeast coast.

A total of 15,881 people are confirmed to have died and 2,668 others remain unaccounted for.

The Emperor paid tribute to those who lost their lives, including the more than 2,300 whose deaths have been recorded as being caused by the stresses of life in evacuation centres or temporary housing.

Schoolgirl Rin Yamane recounted the horror of the day she lost her mother as they tried to escape the waves.

Meanwhile, hundreds of people affected by the Fukushima nuclear crisis in Japan filed a class action lawsuit Monday demanding greater efforts to clean up the contaminated region two years on from the disaster.

Some 800 plaintiffs filed the case with the Fukushima District Court, demanding 50,000 yen ($520) a month each from the government and Tokyo Electric Power Co (TEPCO) until the area is restored, their lawyers said in a statement.