The Mashco-Piro appeared suddenly on the paths snaking through this beautiful, leafy village, armed with nearly seven-foot-long bamboo arrows sharpened to a knife edge.

“Why do you want to kill me?” Shipetiari’s sub-chief, a small but intimidating woman named Rufina Rivera, hollered when she first encountered the Mashco in January.

They continued to visit stealthily. Cooking pots and machetes disappeared from the secluded clusters of raised wooden homes, tucked into the Amazon jungle about a half hour’s walk from the Alto Madre de Dios River. (Read “Some Isolated Tribes in the Amazon Are Initiating Contact.“)

But things would get worse. In March, one took aim at an older woman. Her skirt fluttered as the arrow just missed.

Then, in the beginning of May, when most of the community’s men were across the river helping clear a path for a road, two Mashco parties slipped into the town. One headed to its center; the other to a farm, stealing piles of yucca.

As Venancio Italiano, a community elder, walked with some women and children, an arrow sliced through the air and scratched a bloody streak into the bare chest of a seven-year-old boy. The group fled, stalked from the trail’s edge by the Mashco.

Nearby, Leo Perez and a friend raced to where the intruders had snatched the yucca and took some photos. As Perez squinted at the digital camera, his friend heard the arrow and yelled a warning. But it was too late. The 22-year-old slumped over, impaled, an arrow protruding from his back.

‘Uncontacted’ But Not Unknown

For at least four decades, Peru’s estimated 600 to 800 Mashco have had some contact with settled indigenous communities in the country’s southeast.

View Images ANDREW UMENTUM, NG MAPS SOURCES: RED AMAZÓNICA DE INFORMACIÓN SOCIOAMBIENTAL GEOREFERENCIADA (RAISG); MINISTERIO DEL AMBIENTE (MINAM), PERU

More recently, they’ve hailed boats on the rivers and asked for food, clothing, and tools such as machetes. People from the region say they have been offered Mashco women and babies, have stumbled upon encampments in the jungle, and have fled showers of arrows while fishing. They know that the Mashco aren’t great swimmers but are adept at climbing trees, use two fruits to make booze fermented in bamboo pods, and name themselves after the flora and fauna of the forest.

Within the last year, for unknown reasons, Mashco appearances have increased in frequency and aggression, leading to Perez’s death, the evacuation of two villages, and the intervention of the government.

Peru’s Ministry of Culture now maintains a permanent outpost on the Alto Madre de Dios River, near Shipetiari. Every day, teams of government protection agents patrol the river, meeting with the Mashco when they appear on its rocky shores.

“Our aim is to safeguard the rights to life, health, and self-determination of indigenous peoples,” says Lorena Prieto, who runs the program tasked with managing Peru’s native populations. “We couldn’t wait any longer.”

It’s a complex and rapidly evolving situation. Any early contact with an isolated tribe carries a risk of death for all involved from violence or disease, as jungle immune systems are ill-equipped to handle the flu, measles, or even the common cold.

The government’s plan to make controlled contact has also ignited a storm of consternation from groups who insist the Mashco’s right to isolation must be preserved. But it’s hard to ignore the evidence that the Mashco have already initiated contact.

“Something has shifted,” says anthropologist Glenn Shepard of the Goeldi Museum in Brazil, who has worked with native communities in this region. “These are people who used to make a huge effort to hide and to reject contact, but are now seeking it out.”

Shared Language and Ethnicity

The people who live in Diamante, downriver from Shipetiari, have had sporadic encounters with the Mashco for many years. Here, the Alto Madre de Dios winds down from the mountains, skirting the southern border of Manu National Park. Its tributaries are rich with fish and offer a route to fertile hunting grounds—and to the palm-fronded huts and smoking fires of the jungle nomads.

The Mashco share their ethnicity and language with the Yine people of Diamante and other native communities in the area.

View Images Santos Vargas, shown with his wife Rosa Cusichinari, brought a Mashco child to the village of Diamante in the 1970s. He later offered the child, who became known as Alberto Flores, the opportunity to return to the forest. Flores chose to stay. Photograph by Jeff Cremer

“About 80 percent of what they say, we understand,” says Romel Ponciano, the president of Monte Salvado, which was evacuated in December after a Mashco raid. “The things we don’t understand—the words do exist, but they’re words that older generations used.”

When the Mashco use words such as sawnawle or pyosematanu, Ponciano, who is also a government protection agent, asks the community’s elders for help. Those words—“banana” and “gutting a fish”—are paranta and pshigichkaganro in today’s Yine.

At least one word remains the same, though: “Mashco.” It means “wild ones” or “savages.” As one might expect, the Mashco don’t call themselves Mashco. They prefer the term “Nomole,” which means “brothers” or “countrymen” in both modern and older Yine.

“When you call them Mashco, they get angry,” says Waldir Gomez, who lives in Diamante and has met with them. Miming a hug, he adds, “When you call them Nomole, they feel better.”

For many Diamantinos, sharing a common language and ethnicity means they consider the Mashco to be their brothers. But interactions between the groups are complex and have not always been friendly. One of the best-known encounters was in the mid-1970s, when Santos Vargas and some friends from Diamante met some Mashco near the Río Pinquen. They fired their guns into the air and the Mashco fled. But a Mashco boy stumbled and became stuck.

View Images Alberto Flores is Mashco by birth. He was taken from the forest and brought to live in Diamante when he was a kid, and now speaks Yine, Matsigenka and Spanish. Photograph by Jeff Cremer

“I was playing with my older brother near the river bank. We were climbing trees,” recalls Alberto Flores, a tall, easy-going man with an infectious smile and sharp eyes. “Suddenly, many people surrounded me. My brother jumped into the water because he knew how to swim. He escaped.”

Vargas and his friends kidnapped Flores and took him to Diamante. There, the boy discovered bananas and masato, the fermented cassava beer that is both food and beverage. After about eight months, Vargas offered Flores the chance to return home. By then, the difficult life of a forest nomad was no longer his preference.

“The community is better,” Flores says.

Contact Picks Up

An encounter in 2010 led roughly two dozen Mashco to begin appearing regularly near Diamante, where houses flank a long, pebbled pathway running straight through town. One day, villagers say, Nicholas “Shaco” Flores met a group of Mashco while fishing along the Pinquen. Though he’d seen them in the forests for decades, this time Flores gave the Mashco machetes and told them to follow him back to his farm.

View Images Luis Vargas scans for signs of the Mashco from the government’s patrol boat. Vargas, along with a crew of government protection agents, helps ensure that interactions with the Mashco are safe for the tribe and the area’s residents. Photograph by Jeff Cremer

Over the next year, Shaco Flores continued to give the group whatever they asked for—mostly tools, bananas, and more bananas. Then he stopped, though no one knows exactly why. In late 2011, the Mashco targeted him. Two times, they took aim and missed. The third time, in November, an arrow pierced his heart.

“When they want something, and you tell them no, they threaten to shoot you,” Gomez says. “If you ask them too many questions, or ask a question repeatedly, they get upset.”

The people of Diamante could have avenged Flores’ death. For about a week, heavy rains and a swollen river trapped the Mashco on the island where they’d killed Flores, making them easy targets for those with motorboats and shotguns. “We couldn’t do that,” says Edgar Morales, the community chief. “They are our brethren.”

After a brief disappearance, the Mashco returned. Photos and videos taken over the past three years, but which have only recently gotten attention, show men and boys eagerly hauling machetes and bananas out of passing boats carrying missionaries, loggers, and tourists.

View Images Government protection agents patrol the Alto Madre de Dios every day. In the photo on this camera, Koka carries a pile of bamboo arrows with deadly sharp tips. Photograph by Jeff Cremer

“Contact has been established a lot earlier than any of us imagined,” says Shepard, the anthropologist. “Those photographs show clear, direct contact that’s been going on for years now. What’s new is that it’s not new.”

A Traumatized Village

Perez’s killing earlier this year did not change how Diamantinos view the Mashco.

“It’s a sort of mixture of caution, because they do know that the Nomole are dangerous. But there's also the feeling of reaching out, and integrating them, and curiosity about these 'wild' Yine,” says Frank Hajek, president of SePerú, a nonprofit organization that works with native communities.

But in Shipetiari, where Perez lived, most residents are ethnic Matsigenka. They don’t speak the same language as the Mashco, feel no brotherly ties, and want nothing to do with them.

“And now they’ve landed on their doorstep, acting in a rapidly aggressive way,” Hajek says. “They’re at relatively high risk every day now. Their security, their food security, their income have all been severely hit."

Forced to admit Shipetiari was not safe, the community closed one of its major sources of income, its ecotourism lodge. Guides, cooks and other workers have since scrambled for cash, which they need to send their children to regional schools.

View Images The forests in this region are dense and muddy. There are no roads except for a few paths carved by logging trucks, like the one here. That will change. A new road will eventually connect the regional capital with a major gold mining town. Photograph by Jeff Cremer

Government agents patrol the community’s perimeter every day, looking for broken branches and other telltale signs of visitors from the forest. Walkie-talkies are shared among the families, used for updates and alerts. If the Mashco return, the community plans to shelter in the concrete kindergarten.

Each morning, Rivera and the others listen for news from the government agents. On days when the Mashco come to the beaches near the control post downriver, Rivera says she feels safer, pointing out, “They can’t walk here in one day.”

Government agents have repeatedly warned the Mashco not to return to Shipetiari, but there’s no guarantee they’ll stay away. For now, there’s a kind of uneasy truce.

“If the Mashco don’t come back, we won’t go look for them. If they do come back, we will defend ourselves,” Italiano says. “And then go look for them.”

Meeting On the River

Dozen of steps up a muddy hill between Shipetiari and Diamante, overlooking the Alto Madre de Dios, sits the government’s control post. The building, which had been empty for two years, is now continually occupied by protection agents.

Inside, photos of the Mashco who visit the beaches hang on the walls, along with a hand-drawn map. There’s also a 16-inch-long bamboo tip from a Mashco arrow, sharpened using the teeth of enormous rodents, and a photo of Shaco Flores. A solar panel propped on a chair outside powers the communication equipment.

View Images From a control post on the Alto Madre de Dios, Reynaldo Laureano checks in with other posts on Amazonian rivers. Laureano accompanies government protection agents on their patrols. He speaks Yine and can talk with the Mashcos. Photograph by Jeff Cremer

Until Perez was killed, about two dozen Mashco had been appearing on the nearby rocky beaches fringed with bamboo and palm. They vanished for a while, but returned, at first only in small numbers.

Since May, five Mashco have met regularly with the protection agents, who know them by name: Putgana (“spider”), an older woman who was recently attacked by an anteater; Kamotolo (“wasp”), a man in his late 20s; Yomako (“trogon,” a tropical bird), a pregnant girl in her early teens; Knayi (“tangarana tree”), a boy in his mid-teens; and Koka (“woodpecker”), a nine- or ten-year-old boy who carries the group’s arrows.

For months, the five would say only that the others were “far away,” prompting speculation the clan suffered an epidemic or quiet retaliation. But in August, a sixth Mashco joined them, and now there are more than a dozen. They’ve said they’re reappearing slowly because they’re afraid.

Each day, Ponciano and other protection agents, joined by Reynaldo Laureano and Luis Vargas, from Diamante, motor up and down the river. They prevent boats from stopping along the riverbanks where the Mashco appear, which Laureano says they do about every three days now, asking only for bananas.

The rules of engagement are simple: Give them what they want. Don’t talk for too long. Warn them to stay away from Shipetiari. Meet them in different places to avoid a trap. Don’t ask pointed questions about sensitive subjects, such as Perez’s death.

“The most important thing is discipline, in interaction and in schedule,” says Ponciano. “You have to be careful with your words in these situations.”

View Images Gregorio Perez left Shipetiari after the Mashco killed his son Leo and moved closer to the river, where the fishing is good, bananas grow well, and Leo’s soul isn’t restless. He and his family will probably return when the rains come and the river floods. Photograph by Jeff Cremer

To reduce the risk of triggering a disease outbreak among the Mashco, Ponciano and the others had multiple vaccinations, and a doctor is ready to treat the Mashco at the first sign of sickness. At some point, the protection agents will try to explain why—if the Mashco want to stay in contact with the outside world—it’s important to be vaccinated. But so far, says Ponciano, “They’re strong and healthy.”

‘No Recipe For Success’

What will happen next is anyone’s guess. Peace in the region hinges on whether the government remains engaged and whether its agents win the trust of the Mashco.

“It will require patience, humility, and a willingness to spend years with them to gain their confidence,” says José Carlos Meirelles, who has more than 40 years of experience managing first-contact situations with tribes in Brazil. “It won’t work to repeatedly bring in new teams. The relationships with the indigenous people are personal, not institutional.”

Maybe at some point, we’ll learn why the Mashco have started shedding their forested isolation—whether it’s pressure from loggers or drug traffickers infringing on their territory, a food shortage, disease, conflicts within the tribe, or simply succumbing to temptations dangled by outsiders. Perhaps we’ll also know why the Mashco recently took two lives, and if they’d like to retain their nomadic ways or settle somewhere along the river.

“How do we receive them without killing them culturally or physically? We are learning,” Meirelles says. “We have to accompany the process, staying with them so that their entry in our world is less painful. There is no recipe for success.”