The 1976 Tangshan earthquake, also known as Great Tangshan earthquake, was a natural disaster resulting from a magnitude 7.6 earthquake that hit the region around Tangshan, Hebei, People's Republic of China on 28 July 1976, at 3:42 in the morning. In minutes the city of Tangshan, an industrial city with approximately one million inhabitants, ceased to exist. Eighty-five percent of the buildings in the city collapsed or were unusable, all services failed, and most of the highway and railway bridges collapsed or were seriously damaged. At least 242,000 people died (some have said three times that), making this the third (or possibly second) deadliest earthquake in recorded history.

Tangshan was the most notable of several disasters in 1976, which in Chinese tradition might signal that the government had lost political legitimacy. The Tangshan earthquake also came without warning, undermining a key tenet of Maoist ideology, that earthquakes could be predicted. Nonetheless, the government's response showed that it was prepared and competent to quickly provide relief.

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