Chinese archaeologists said Thursday that they have completed a three-month excavation of six clusters of ancient tombs in Chongqing Municipality.

The clusters, consisting of 25 tombs, were discovered in an industrial park in Huanggu Village. They are believed to be from the Southern Song (1127-1279) and Ming (1368-1644) dynasties, according to a spokesperson with Chongqing Cultural Heritage Research Institute.

The tombs cover an area of more than 1,600 square meters, nearly the size of four basketball courts.

Archaeologists said that they are most interested in seven double-chamber stone tombs that have high quality building materials and delicate carved interiors, which show the status of the tomb owners.

A total of 38 burial artifacts such as porcelain objects were also discovered during the excavation which started in late July.

Archaeologists hope to learn more about burial customs during the periods.