1976 Tangshan Earthquake

At 3:42 a.m. on 28 July 1976, a 7.6-magnitude earthquake struck the industrial city of Tangshan in Hebei Province, China, while nearly 1 million residents slept. The city was almost entirely levelled within 23 seconds; official figures cited 242,000 deaths, though some estimates place the toll at over 650,000. A major aftershock of 7.1 struck 16 hours later. The disaster struck during China's Cultural Revolution, and the government initially refused foreign aid, hampering the rescue effort.