Chinese archaeologists said they had discovered another important site of human activity dating back 300,000 to 500,000 years, roughly contemporary with Peking Man.
Dozens of stone, animal bone and horn tools have been excavated at a limestone quarry site in Luotuo Hill in the coastal city of Dalian, Liaoning Province.
Researchers have obtained more than 1,000 important samples since the joint excavation began in August by the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences and the Dalian Natural History Museum.
Stone tools and large herbivorous animal bones that appear to have been cut or smashed by humans show the site was an important site for early human activity, said Huang Weiwen, researcher with the institute, on Saturday.
Deer and antelope horn tools were also used at the Zhoukoudian Caves in Beijing's suburbs, where the skulls of Peking Man, or Homo erectus, were found in the 1920s and 1930s.
Peking Man was first believed to have lived in Zhoukoudian about 400,000 to 500,000 years ago. But some Chinese scientists later said they were actually 200,000 years older, probably from a mild glacial period.
"The discovery of the Luotuo Hill site of early human beings is of great significance," said Gao Chunling, deputy head of the Dalian natural museum.
It is likely to be the earliest cultural ruins in northeast China, making it important for the study of human evolution and the origin of culture in the region, said Gao.
Fossils of ancient mammals such as elephants, tigers and wild boars were also similar to those unearthed at Zhoukoudian, according to the researchers.
Yet no fossils of human bones or teeth have been unearthed at the site yet. The excavation work is still under way.
The local limestone geography, where cracks and water-eroded caves formed easily, provided a good location for the preservation of early human and mammal fossils, according to Liu Jinyuan, a paleontologist with the museum.
Workers are registering the unearthed samples for further study.