Also known as the Tokyo-Yokohama earthquake of 1923, the Great Kanto Earthquake is considered to be the worst natural disaster to strike Japan. With a magnitude of 7.9, the earthquake struck the Tokyo-Yokohama metropolitan near noon on September 1st, 1923. An estimated 140,000 died; this includes 44,000 civilians who had sought refuge near the Sumida River in the first few hours, only to be burned by the "dragon twist," a freak tornado of wildfire caused by the earthquake. An ensuing forty-foot-high tsunami swept away thousands of more people.