The Marunouchi district of Tokyo after the 1923 earthquake
1923: The massive earthquake that struck Tokyo, Yokohama and surrounding areas on 1 September killed as many as 140,000 people, injured 100,000 and damaged or destroyed the homes of more than 3 million. The tremors themselves destroyed less than 1 per cent of homes in the Japanese capital, but fires that raged for almost two days destroyed a further 62 per cent.
Stunned by the magnitude of the disaster, many Japanese believed rumours that Koreans were deliberately starting fires, looting shops and houses, and poisoning wells. Gangs of Japanese vigilantes, egged on by irresponsible government announcements, attacked Koreans. The police reported that 231 Koreans were killed and 43 injured.
Source: Michael Weiner, The Origins of the Korean Community in Japan 1910–1923 (1989), chap. 6