Greenpeace angered the Peruvian government last week when some of its activists trekked through Peru's ancient Nazca Lines — a UNESCO World Heritage site — to stage a publicity stunt timed to coincide with UN climate change talks being held in the South American nation's capital of Lima. The stunt resulted in calls for legal action, and officials have since released new drone footage showing the extent of damage caused at the site.

Released exclusively to PBS NewsHour, the video provides visual evidence of the impact the early morning operation had on the centuries-old geoglyphs, which have been preserved thanks to the arid climate of the desert site located 200 miles south of Lima.

While a spokeswoman for Greenpeace said the group was "absolutely careful" when rolling out the banner, the video proves otherwise. Provided by Peru's Culture Ministry, the footage depicts an aerial view of new lines that showed up after the activists laid their "Time for Change!" sign next to a hummingbird etched into the desert. These new path lines were created after 20 members of the environmental group hiked their way to the site, which is not open to the public, the government said.

Courtesy PBS

Also visible in the drone video are lines around where the message was laid out, and what appears to be the outline of the letter "C" that forms part of the word "Greenpeace" included in the banner. According to NewsHour, the footage could be used in legal proceedings, if the government decides to pursue action.

The widely discussed publicity stunt follows a separate Greenpeace project executed in early December, when the group projected a message promoting solar energy on the ancient Incan ruins of Machu Picchu in Peru.

Nazca is a notoriously sensitive ancient site, where a single step can cause irreversible damage. The unique look of the lines is attributed to the contrast of the black rocks that rest atop white sand. Typically, tourists have to pay for flight tours if they want to get a view of the giant drawings that take the form of various animals and plants etched into the ground.

"They are absolutely fragile," the country's culture minister Luis Jaime Castillo told BBC. "They are black rocks on a white background. You walk there, and the footprint is going to last hundreds or thousands of years. And the line that [Greenpeace has] destroyed is the most visible and most recognized of all."

Castillo has threatened to sue the group members who participated in the event. Participants included citizens from Chile, Germany, Brazil, Austria, Argentina, and Spain.