Visitors watch photos of the school before the disaster displayed at the ruins of the Okawa Elementary School in Ishinomaki, Japan, March 9, 2021. A public elementary school in Miyagi Prefecture lost more than 80 lives in the tsunami following the March 2011 earthquake in northeastern Japan. Ten years on, the ruins of the school building still tell the unimaginable tragedy of the calamity. (Xinhua/Du Xiaoyi)

Photos of the school before the disaster are displayed at the ruins of the Okawa Elementary School in Ishinomaki, Japan, March 9, 2021. A public elementary school in Miyagi Prefecture lost more than 80 lives in the tsunami following the March 2011 earthquake in northeastern Japan. Ten years on, the ruins of the school building still tell the unimaginable tragedy of the calamity. (Xinhua/Du Xiaoyi)

The ruins of the Okawa Elementary School is seen in Ishinomaki, Japan, March 9, 2021. A public elementary school in Miyagi Prefecture lost more than 80 lives in the tsunami following the March 2011 earthquake in northeastern Japan. Ten years on, the ruins of the school building still tell the unimaginable tragedy of the calamity. (Xinhua/Du Xiaoyi)

A visitor takes photo of the ruins of the Okawa Elementary School in Ishinomaki, Japan, March 9, 2021. A public elementary school in Miyagi Prefecture lost more than 80 lives in the tsunami following the March 2011 earthquake in northeastern Japan. Ten years on, the ruins of the school building still tell the unimaginable tragedy of the calamity. (Xinhua/Gang Ye)

The ruins of the Okawa Elementary School is seen in Ishinomaki, Japan, March 9, 2021. A public elementary school in Miyagi Prefecture lost more than 80 lives in the tsunami following the March 2011 earthquake in northeastern Japan. Ten years on, the ruins of the school building still tell the unimaginable tragedy of the calamity. (Xinhua/Du Xiaoyi)

Flowers are laid in front of the ruins of the Okawa Elementary School in Ishinomaki, Japan, March 9, 2021. A public elementary school in Miyagi Prefecture lost more than 80 lives in the tsunami following the March 2011 earthquake in northeastern Japan. Ten years on, the ruins of the school building still tell the unimaginable tragedy of the calamity. (Xinhua/Du Xiaoyi)

Flowers are laid in front of the ruins of the Okawa Elementary School in Ishinomaki, Japan, March 9, 2021. A public elementary school in Miyagi Prefecture lost more than 80 lives in the tsunami following the March 2011 earthquake in northeastern Japan. Ten years on, the ruins of the school building still tell the unimaginable tragedy of the calamity. (Xinhua/Du Xiaoyi)