SHIJIAZHUANG, Oct. 5 -- Chinese archaeologists said they have discovered more than 2,000 paleolithic relics such as stone tools and ostrich egg ornaments left by humans at north China's Nihewan ruins area.

The paleolithic ruins found at Xishuidi Village, Yangyuan County in Hebei Province include mammal bone pieces, three ash sites and burnt bones, which are evidence of human activity dating back more than 13,000 years, said Guan Ying, a paleoanthropologist from the Chinese Academy of Sciences and head of the excavation team.

The new findings proved again the existence of human beings since ancient times in the Nihewan area along the banks of the Sanggan River.

The ruins of the Nihewan Culture are located between the counties of Yangyuan and Weixian in Hebei, which is well-known for the discovery of mammal fossils and Old Stone Age remnants. Ancient people may have lived in the area some 1.9 million years ago.

Since the 1920s, both Chinese and foreign archaeologists have conducted in-depth studies on Nihewan Culture ruins, which have led to a series of important discoveries.

In 2001, traces indicating early humans had eaten there were found at the ruins, challenging the theory that mankind originated in Africa.

Excavation work is under way at the new site.