Newly built villas in the special protection area of the Sun Yat-sen Mausoleum scenic spot in Nanjing, capital of East China's Jiangsu province, are illegal, officials said on Monday.

The officials said the developer had not obtained the proper approval from authorities to build the villas.

Construction of the villas by Jiangsu Deji Group inside the Sun Yat-sen Mausoleum scenic spot, which is a national natural and cultural heritage site, took more than a year, State broadcaster China Central Television (CCTV) reported.

But according to regulations, commercial real estate development inside the area has been banned since 2004. Construction and extensions for other purposes must be approved by authorities including the scenic site's administrative bureau.

"Construction of the new villas was never declared to the administrative bureau of Sun Yat-sen Mausoleum scenic spot, nor was it approved by the city's planning authority," said Liao Nan, head of the publicity department of the bureau.

"The bureau issued four shutdown notices to the developer, but they refused to cooperate," he said.

Deji Group kept the bureau at bay by building a wall around the villas and claiming the area was under military control.

In the CCTV report, several men holding sticks to stop cameramen filming claimed that the area was part of the military administrative zone.

A man surnamed Chen asked a cameraman to delete what he had filmed and said "the villas were related to State secrets" and shooting State secrets would mean that the cameramen would be considered "spies".

But Hao Xiaohua, an official at the real estate management bureau of Nanjing Military Region, told CCTV that the area on which the villas were built had not been under military control since 1992 when authorities gave approval for the land to be used for the building of 16 villas in cooperation with another local real estate developer.

Four of the 16 villas were sold to individuals, while Deji Group bought the rest for 3 million yuan ($452,000) each. Since 2009, the group encircled the land with walls, tore down the 12 old villas and started building more new villas for sale.

Du Haiyan, owner of one of the four villas, told Jiangsu Television that the developer has built more than 40 new villas in the neighborhood so far. The selling price of each villa will be between 40 million yuan and 50 million yuan, bringing the group great profits.

Jiangsu Deji Group could not be reached for comment on Monday.