Original: It was the deadliest earthquake to hit China since the 1976 Tangshan earthquake , which killed at least 240,000 people , and the strongest since the 1950 Chayu earthquake in the country , which registered at 8.5 on Richter magnitude scale .
Simplified: It was the deadliest and strongest earthquake to hit China since the 1976 Tangshan earthquake , which killed at least 240,000 people .