Peru has increased surveillance at popular archeological sites to counter a new trend of tourists taking nude photos at Machu Picchu.
Tourists have been posting the naked pics on blogs, prompting a statement from the cultural ministry rejecting "any disrespectful act committed by visitors" to the historical sites.
"We have redoubled efforts for continuous surveillance and monitoring of the site," so security personnel can intervene to stop the exhibitionist photography, it said.
The ministry called on visitors to help protect the historical sites and to "be alert to this kind of attitude that's solely aimed at getting attention."
A video posted on YouTube showed two tourists streaking at the Incan site. According to the Huffington Post, the offenders seen in the video were Australian Sydney Rudevies Liam Timothy and New Zeleander Topp Mathew Jared.
Authorities are also worried over a recent spate of graffiti attacks.
Last week, the famous 12-Angle Stone - an example of intricate Incan masonry and design - was hit with spray paint, police said.
The suspect has been fingered in several other attacks on archaeological sites, they added.
"Although there are new techniques for erasing, the paint used could leave irreversible consequences for the most important stone in the Inca Roca palace," a spokesman from the cultural ministry in Cusco said.
Ricardo Ruiz Caro, head of the ministry, told reporters that in the first three months of 2014, "four similar spray-paint incidents have been recorded, adding to 33 remembered in 2013," including one at the key tourist site at the Incan Imperial City.
The official announced the relaunch of the "Heritage Watchers" program, with the support of universities, schools and neighboring communities, in a crusade to defend the country's heritage.
Under Peruvian law, unauthorized destruction, alteration, sale or removal of any of the country's archaeological treasures is punishable by three to eight years in jail and a fine.