The 8.5-magnitude Haiyuan Earthquake that shook northwest China in 1920 killed about 273,400 people, over 40,000 more than previously estimated, a Chinese seismologist said Thursday.

The epicenter of the quake was Haiyuan County, in Ningxia Hui Autonomous Region, but it also rocked neighboring Gansu and Shaanxi provinces, on Dec. 16, 1920, said Deng Qidong, an academician with the Chinese Academy of Sciences, at a seismological seminar on the earthquake.

"The Haiyuan Earthquake was the largest quake recorded in China in the 20th Century with the highest magnitude and intensity," said Deng.

More than 70,000 people died in Haiyuan County alone, accounting for 59 percent of the county's total population.

Subject to economic and transportation conditions of that time, the total number of dead was not calculated until 1921 when seismologists were sent to Haiyuan for field research.

Seismologists concluded that the death toll was 230,000 and this figure has since been widely cited.

The previous death toll was based on research in 64 counties in Ningxia and Gansu, where the damage was most severe, said Deng.

The latest study of the earthquake, led by Zhang Siyuan, director of the earthquake administration of Ningxia, explored more areas that covered 13 additional counties in Shaanxi Province.

Zhang said the research team obtained more materials and records on the earthquake.

After a thorough examination and cross-checking, the research team proposed a death toll of 273,400.

Dec. 16 marked the 90th anniversary of Haiyuan Earthquake, which affected an area of 20,000 square km.

More than 1,000 government officials and residents from Ningxia gathered Wednesday at the foot of Nanhua Mountain in Haiyuan County to remember the disaster.

Also on Wednesday, the Haiyuan Earthquake Museum was opened to the public with numerous relics and collections of papers and materials on display.

(Source: Xinhua)