GUIYANG, May 4 (Xinhua) -- Ancient documents of the Miao and Dong ethnic groups in southwest China's Guizhou Province need protecting as they are being ruined from natural and man-made disasters.

The documents, called "Jinping Writs", refer to the original records of contracts, account books, government reports, genealogy and county regulations in Jinping and its neighboring counties in Guizhou.

Wang Kui, director of the archives in Jinping County, said that the records date back to as early as 1546 during the Ming Dynasty (1368-1644), and the contents related to subjects including economy, history, law and ethnology among other areas.

The documents are important in the research of politics, economy, culture and social development of the local ethnic groups, Wang said.

Besides natural disasters like fires, floods and moth damage, Jinping Writs have been smuggled out of the region and lost to other countries, according to Wang.

Statistics from the county's archives showed that over 100,000 Jinping Writs used to be in the hands of local people.

The county started to collect the ancient documents in 2000. Protection work was strengthened in 2010 when Jinping Writs were listed as documents of heritage by the State Archives Administration.

By the end of 2013, the county had collected over 50,000 Jinping Writs. Over 20,000 documents have been digitalized for further preservation and research.

About 19 million yuan (3 million U.S. dollars) has been invested to build a museum for the ancient documents.

Wang said they need more money to collect more documents. It is estimated that over 50,000 Jinping Writs are still being kept by locals in 200 villages of the county. But some villagers are unwilling to hand over the documents.