Japan observed a moment of silence Sunday, to mark the first anniversary of the earthquake and tsunami that struck Japan last year, leading to one of the worst nuclear crises in history.

Emperor Akihito led millions in mourning and prayer Sunday at a televised ceremony from Tokyo. The ceremony marked the exact minute the 9.0 magnitude quake struck – 2:46 p.m.(0546 UTC) – unleashing the deadly wave that killed more than 19,000 people and left around 3,000 missing. Ceremonies and private observances were also held around the disaster zone on the northeast coast.

The wave struck the Fukushima Dai-ichi nuclear power plant, causing three reactors to melt down and leaving some tracts of land uninhabitable for decades to come because of radiation levels. A year later, people are still living in temporary shelters, many of them still unemployed, as they struggle to put their lives back together.

Meanwhile, around 50 anti-nuclear protesters gathered Sunday in front of the headquarters of Tokyo Electric Power Company, operator of the crippled power plant at Fukushima. They chanted slogans demanding all nuclear plants be shut down and the nation's largest utility be broken up.

Japanese Prime Minister Yoshihiko Noda wrote in The Washington Post Saturday that Japan will forget neither the people lost in the disaster nor the outpouring of support from other nations after the event. He said Japan is “deeply indebted” and “forever appreciative.”

Much of Japan's worst-hit areas are now clear of debris, but the extent of the damage is such that it may take many years before some regions can start rebuilding.