Former Japanese prime minister Yukio Hatoyama visited the memorial hall on Jan 17, 2013, observing a moment of silence in front of the monument erected to the memory of the victims. He also planted a ginkgo tree in the peace park.
Hatoyama wrote the Chinese characters for fraternity and peace on a wall and changed one character of his signature to a Chinese character that means "friend".
Hatoyama was Japan's prime minister from 2009 to 2010.