International environmental organization Greenpeace apologized for the publicity stunt that some of its members did in the heritage site Nazca lines in Peru.

The Nazca lines are a series of ancient geoglyphs located in the Nazca desert in Peru. It has large designs of hummingbirds, spiders, monkeys, fish and other animals that could be around 1,500 to 2,000 years old. Locals consider it sacred and believe that the ancient Nazca people drew them for the gods to see from the sky.

The ancient site now has another attraction after 20 Greenpeace activists placed a yellow cloth banner beside the hummingbird saying "Time for Change. The future is renewable. Greenpeace."

The Peruvian government is not happy about the seemingly peaceful protest and said that it would sue the activists for damaging the Nazca lines. The authorities said that the activists did not only trespass on the ancient site but also damaged it. The locals also condemned the group and said that what Greenpeace did was a "moral offense," according to BBC News.

Deputy culture minister Luis Jaime Castillo called it a "slap in the face at everything Peruvians consider sacred."

Greenpeace apologized for the incident and promised to work with the Peruvian government in the investigation. The activists argued that they were careful when they placed the cloth, but the authorities said that the group left footprints, The Independent reported.

"Without reservation Greenpeace apologizes to the people of Peru for the offense caused... We are deeply sorry for this," the statement reads.

"We fully understand that this looks bad. Rather than relay an urgent message of hope and possibility to the leaders gathering at the Lima UN climate talks, we came across as careless and crass.

"We have now met with the Peruvian culture ministry responsible for the site to offer an apology. We welcome any independent review of the consequences of our activity. We will co-operate fully with any investigation."