Across Japan, people paused to observe a minute of silence at 2:46 p.m. in memory of the devastating tsunami and earthquake that hit the country three years ago.
The disasters, known in Japan as "3-11," left tens of thousands dead and triggered a nuclear crisis. It was the strongest quake ever recorded in Tokyo's history.
Survivors held memorial events throughout the nation. Yukari Tanaka, a resident of Futaba town, where the Fukushima Dai-ichi plant is located, spoke at one ceremony.
"I never forget how I regretted that I had to evacuate, leaving my father behind," Tanaka said of her deceased father.
Emperor Akihito said that his heart breaks when he thinks of the Fukushima residents who have no idea if they can ever return home.
"Many disaster survivors are still experiencing difficulties. It is important that all people of Japan unite their hearts and stand by each other for a long period so that they can live without losing their hopes and in good health," Akihito said at the ceremony.
The country has struggled to rebuild and clean up radiation from meltdowns at Fukushima Dai-ichi nuclear power plant. About 270,000 people are still displaced, and many might never be able to return home because the radioactive contamination is making their towns off-limits.
Japan has put aside $250 billion for the reconstruction expected to last until 2016. The power plant's decommissioning is expected to take about 40 years.