Search and rescue teams in Indonesia are scouring rubble for survivors, with 222 people confirmed dead, 843 people injured and 28 missing.
AFP takes a look at the five deadliest tsunamis recorded over the past century.
"It's nearly impossible for the principal and other teachers, who are not anti-disaster experts, to predict a tsunami," Masato Chiba said.
Some 170,000 lives were lost in the country when a 9.1-magnitude "megathrust" quake struck Aceh.
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