Greenpeace is keeping mum when it comes to the identities of activists who displayed their message among the ancient Nazca Lines, leaving marks that officials call permanent. A drone investigation reveals the damage, which Peru's culture minister calls "irreparable," saying that "the apologies offered by the environmental group aren’t enough," the Wall Street Journal reports. She says the government plans to sue Greenpeace. The 20 activists displayed a message calling for renewable energy alongside an enormous etched hummingbird. When Peru asked Greenpeace for the activists' identities, "the answer was that they don’t know the names," says an official. "That seemed like a joke to us."
But Greenpeace says it is taking action, the New York Times reports. "Everyone who was involved will be approached and asked to account for their role,” the group says in a statement. “Until we have carried out a proper investigation we cannot comment on any individuals." Meanwhile, a photographer says the activists, apparently led by an archaeologist, were careful. "The archaeologist explained where to walk and where not to walk," the photographer says. "There was a great concern not to even leave a mark of your shoes on the ground, and if a rock was moved, put it back in its place."