The 1854 Nankai earthquake occurred at about 16:00 local time on 24 December. It had a magnitude of 8.4 and caused a damaging tsunami. More than 30,000 buildings were destroyed and there were at least 3,000 casualties. It was the second of the three Ansei great earthquakes; the 1854 Tōkai earthquake of identical magnitude had hit northwest the previous morning, and the third 1855 Edo earthquake would strike less than a year later.