The director of the Palace Museum said at a press conference in Beijing on Tuesday that the museum has collected evidence from 20 sets of cameras of the controversial nude photo shoot at the former imperial complex.

Photos featuring a nude female model at the Forbidden City, also known as the Palace Museum, circulated online in May and caused a heated debate. [Photo/Weibo.com]

Pictures showing a naked model leaning on a white marble handrail and sitting on the head of a marble dragon at the Palace Museum, former home of Chinese imperial family, went viral and caused heated debate on the Internet last month. The photos were first posted on China's microblog site Sina Weibo by photographer Wang Dong on May 17.

Shan Jixiang, director of the Palace Museum, first responded to the incident at a tourism safety press conference held at the Forbidden City.

"Twenty sets of cameras recorded all the actions of the four young people who were involved in this nude photo shoot incident, from buying tickets to taking off the model's clothes and taking photos," Shan said, "The evidence has been given to the authorities to deal with."

He said the Palace Museum management has completed 75 percent of the work to install an all-seeing eye monitor system and has put cameras in 27 zones of the Palace Museum since March 2014. After the work is finished, 2,100 sets of cameras will cover every corner of the Forbidden City, and monitor it 24 hours a day.

Shan also appealed to visitors, saying that the museum is "a sacred place," and asked people to obey social morality and protect the cultural heritage site and its dignity.

"We very much welcome artists from all over the world to make artistic creations. But the indecent photo shoots not only go against social morality, order and good customs, but also harm the relics and the dignity of the cultural heritage. This should be condemned by all society."

The Palace Museum has handed over evidence to the police for further investigation. China's public security law stipulates that those who molest others or purposefully appear naked in public may be subject to five to ten days in police custody. Whether the young people involved in this nude photo are subject to such a punishment will be decided by the public security system, the museum said.

In previous reports, the photographer who took the photos, Wang Dong, whose online name is "WANIMAL," insisted that the photo shoot was an act of artistic creation that did not affect any other visitors to the site.

"I published my photographs on various professional platforms overseas," Wang said. "Some people stole the photos and posted and spread them online and then said I offended them. I thought it was so ridiculous."