Archaeologists work at the excavation site in Yizhuang on Sunday. Wang Guibin / for China Daily

At least 10 ancient tombs were discovered at an ongoing construction site in the Beijing Economic and Technical Development Zone, South Beijing, according to media reports.

The tombs were discovered at the construction site of an apartment building project where Liangshuihe No 1 Street and Boxing No 7 Street meet, in Yizhuang, South Beijing's Daxing district.

They are thought to be tombs from the Han Dynasty (206BC-AD 220), based on the results of the initial excavation, Song Dachuan, head of Beijing Cultural Relic Institute, told Beijing News on Monday.

According to archaeological experts, who were working on site, the cluster of ancient tombs could all belong to one ancient family based on their sizes and styles and the relics and human bones excavated. Though Song did not confirm this.

Security guards now protect the area, which has been isolated, and archaeologists are undertaking a 24-hour excavation while construction is still continuing in other parts of the site.

One employee representing the developer of the project said they invited the archaeological experts to do research at the beginning of this year, because they knew the area might contain burial sites and ancient tombs.

So far, Yizhuang, where the economic zone is located, has reported several discoveries of ancient tombs.

In 2003, it was reported that hundreds of ancient tombs were discovered near Maju Bridge in the economic zone, and the history of most of the tombs could be traced back to the Han or Tang Dynasties.

Some ancient tombs were also discovered in a nearby area in 2004 and again in 2007.

Beijing is believed to have a wealth of cultural heritage still buried beneath the city, however, between 2007 and 2008 though there were 4,191 projects approved in the city, only 2.3 percent of them had an archaeological investigation before construction commenced, according to a previous research report released last December.

By Qin Zhongwei

Editor: Liu Fang