When he was arrested at the U.S.-Mexico border in early June, 24-year-old Mario Perez-Domingo was hoping to save himself and his young daughter from rampant persecution against indigenous communities in his native Guatemala.

But Mario was nearly permanently separated from his 2-year-old child, the kind of terror he couldn’t imagine even in his home country, simply because no one could understand his plight.

When he was apprehended by U.S. Customs and Border Protection near McAllen, Texas, Mario was almost immediately separated from his daughter by the arresting agent, despite the birth certificate stating their kinship and his desperate pleas that she was his child.

Those pleas went unheard—in part because Mario speaks Mam, a language indigenous to Guatemala, and has minimal understanding of Spanish or English. He couldn’t understand where the border patrol agents were taking his daughter or ask whether he would see her again.

It took more than two months, as well as a DNA test and verification of the birth certificate by the Guatemalan consulate, for attorneys at the Texas Civil Rights Project to reunite Mario with his daughter.

“It proves the government’s carelessness when it comes to these families and demands more clarity about why some families are being reunited while others remain separated,” said Efrén Olivares, director of the Texas Civil Rights Project’s racial and economic justice program.

That lack of preparation has resulted in dozens more stories like Mario’s, where people fleeing from violence perpetrated on indigenous populations in Central America have found themselves victimized anew by a system unable to handle indigenous language speakers.

Their children are believed to be among the more than 550 who remain separated from their parents—hundreds of whom have already been deported from the United States, nearly two months after a federal judge ordered the Trump administration to reunite thousands of families that had been separated by its “zero tolerance” immigration policy.

The administration has argued, in a remarkable act of chutzpah, that non-profit organizations should take the lead in tracking down those parents, at least 139 of whom are currently still missing somewhere beyond America’s borders. But a task that humanitarian workers call “extremely difficult” under the best of circumstances has been complicated even further by a language barrier that has isolated immigrants like Mario even within their home countries.

A disproportionate number of these separated parents are in the same position as Mario: they come from indigenous communities, members of persecuted minority groups whose primary language isn’t Spanish, but one of dozens of indigenous languages native to Central America. These groups face unique disadvantages both in their countries of birth and upon entering the the United States—but their greatest vulnerability, advocates say, may be the linguistic barrier that hinders reunification with their children.

“There just aren’t that many interpreters available,” Michelle Brané, director of the Women’s Refugee Commission’s migrant rights and justice program, told The Daily Beast. “The fact that the parents have already been deported, and that a lot of [family reunification efforts] are going to have to happen by phone, mixed in with the language difficulties, makes this a life-or-death issue.”

Americans can be forgiven for assuming that almost all unauthorized immigrants in the United States are originally Spanish speakers of Mexican extraction. President Donald Trump certainly appears to be under that impression: Trump has tweeted about illegal immigration from Mexico fourteen times more than the rest of Latin America combined.

But undocumented immigration from Mexico has declined in recent years, both in the number of migrants and as a percentage of the overall undocumented population of the United States, while the greatest increase in unauthorized entries has its origins in Central America’s “Northern Triangle”: El Salvador, Guatemala, and Honduras.

U.S. Immigration and Customs Enforcement declined to share the most recent statistics regarding the primary language of deported parents, although an ICE report found that of the total number of migrants removed from the United States by ICE in 2016 and 2017, one in three came from El Salvador, Guatemala, or Honduras, and a 2015 review of difficulties faced by indigenous language-speaking immigrants found that 42 percent of Guatemalan families entering Arizona in 2015 spoke an indigenous dialect as their primary language.

Of immigrants fleeing a marked increase in gang violence, internal displacement, and government oppression in the region, an outsized percentage come from indigenous communities whose long history of persecution make them particularly vulnerable to deteriorating government stability in their home countries—and the rise in violence that has accompanied it.

“It’s already difficult for an average person in these countries to get any sort of response from the police to violence, as it is,” said Daniella Burgi-Palomino, the senior associate for Mexico, border and migration issues at the Latin American Working Group, a non-profit that advocates for human rights and conscientious U.S. policy in Latin America.

Those challenges, Burgi-Palomino told The Daily Beast, “are compounded and doubled and tripled for members of indigenous communities because of language issues—and because they have already been historically excluded from government and government responses.”

The language barriers are a contributing factor not only in difficulties indigenous Central Americans face in the United States, but also in their attempts to seek asylum or refuge in the United States in the first place.

“They’re cut off, even in their own countries, from government protection,” Brané said, “which can increase their need for asylum.”

The global number of asylum seekers from the Northern Triangle increased five-fold between 2012 and 2015, according to the International Organisation for Migration, and the number of U.S. residents born in one of the three countries more than doubled between 2000 and 2015, from 1.5 million to 3.4 million. Of those, the Pew Research Center estimated that roughly 55 percent were undocumented.

Migrants of all ethnic and linguistic groups are fleeing the region due to a precipitous rise in gang violence, economic woes, and the current unavailability of government support, Burgi-Palomino said. But indigenous communities are particularly susceptible to those problems—in part because of a history of state-sponsored violence against them.

In Guatemala, the U.S.-backed government waged a 36-year civil war against ethnic Maya peasants who were accused, often inaccurately, of aligning with communists insurgents. A United Nations commission later determined that the state-perpetrated violence against indigenous Guatemalans reached the level of genocide, with roughly 200,000 killed or “disappeared” over the course of the war.

Although an agreement signed at the end of the civil war declared that “all the languages spoken in Guatemala deserve equal respect” and vowed pro-indigenous government policies, most of the promised reforms have failed to materialize.

“Indigenous communities have historically been excluded and targeted against by the state, and continue to be so,” Burgi-Palomino said. “They’re still largely living in the most impoverished parts of the country… Having representation from the indigenous communities in government is still largely a challenge across the board.”

In Guatemala, that isolation has led to strained access to state benefits, including healthcare, nutrition, and schooling, as well as made indigenous communities uniquely susceptible to violent crime—particularly domestic violence.

“One of the main drivers for migration, specifically for indigenous communities out of Guatemala, is domestic violence and violence against women,” Burgi-Palomino said. Alongside Honduras, Guatemala has some of the highest rates of sexual and gender-based violence in the world, which, as The Daily Beast has reported, impacts women in isolated and underserved indigenous communities in particular.

“You’re talking about a population that is extremely vulnerable, and that vulnerability is compounded if you’re talking about an indigenous woman or indigenous child,” Burgi-Palomino said.

In both Guatemala and Honduras, indigenous communities are further threatened by internal displacement, often at the hands of multinational corporations building hotels and resorts who aren’t above using hired mercenaries to push Maya communities off their lands—sometimes violently.

In 2016, activist Berta Cáceres Flores, founder the National Council of Popular and Indigenous Organizations of Honduras, was found murdered in her home after publicly opposing a hydroelectric dam that would threaten a river sacred to the indigenous Lenca people. Two weeks later, a colleague was murdered as well.

“The overarching transversal challenges and human-rights violations that indigenous communities face, both in Honduras and Guatemala, are often directly related to their right to their lands,” Burgi-Palomino said. “It is widely documented that Guatemala and Honduras are two of the most dangerous countries in the world for environmental defenders.”

These dangers, compounded by weak governments with little interest in protecting minority groups, have lead to a massive influx of undocumented indigenous people from the Northern Triangle. Immigration from the region rose by 25 percent between 2007 to 2015, a Pew Research Center analysis of U.S. census data showed, while immigration from Mexico decreased by 6 percent during the same period.

Indigenous immigrants are typically poorer, less educated and are less likely to speak English, making their lives in the United States nearly as isolated as in their home countries. Data from the 2010 census showed that 77 percent of U.S. residents who speak Mayan languages at home said that they speak English “less than very well.” For those who speak Spanish at home, 43 percent said the same.

These disadvantages have been acutely felt by immigrants who speak indigenous languages and have been detained by U.S. immigration authorities. Although a U.S. Immigration and Customs Enforcement “Language Access Plan” released in 2015 declared that efforts were underway to “improve the language services provided in ICE residential facilities,” advocates told The Daily Beast that they have serious concerns about how the language barrier has impacted family separation.

“We know that it’s a pretty major problem,” Brané said. “From having worked with these families in the past, a lot of them speak a little bit of Spanish—they will answer you, they will nod.” But, she added, many are not nearly fluent enough to give informed legal consent to give up their right to be reunited with their child.

The problem isn’t new to the recent influx of indigenous language speakers: one review of adults arrested on the Arizona border in 2014 found that half of those detained described not receiving an explanation of the legal papers issued to them in a language that they actually understood.

“I find it hard to believe that this was adequately explained in every case,” Leah Chavla, an international human rights lawyer and policy advisor with the Women’s Refugee Commission, told The Daily Beast. “There were definitely not enough [translators] for something like this, and I find it hard to believe that this was adequately explained in every case.”

The lack in qualified translators who speak languages indigenous to the Northern Triangle will only become a larger problem in the future, if current trends are any indication. According to statistics compiled by the Department of Justice, Mam, a Mayan language native to Guatemala, is now the ninth-most frequently spoken language in U.S. immigration court cases, followed by K’iche’, another Guatemalan indigenous language, making both more frequently heard in immigration courts than French or Korean. In 2012, neither dialect was even in the top 25 most spoken language in such proceedings.

Without enough translators to handle the caseload of indigenous speakers, immigration courts and asylum proceedings have often forged ahead in Spanish, or taken to “relay interpreting,” a high-stakes version of the playground game “Telephone,” where a migrant’s testimony is translated from Mam or K’iche’ or Q’anjob’al into Spanish, then translated from Spanish into English and back again.

In the midst of the family separation crisis, some speakers of indigenous languages have come forward to volunteer their own interpretation services, Brané said, “but how many of those people are qualified to do technical interpretation?” Additionally, many speakers may be undocumented themselves, making an immigration proceeding the last place they want to be seen.

Advocates see the government’s inability to provide translators in the proceedings as a violation of constitutional protections of procedural due process rights—and a recipe for permanent family separation if deported indigenous parents can’t be located after leaving the country.

“People fled a very specific danger,” Burgi-Palomino said. “The danger was probably in existence for a long period of time. Now, they’ve been forced to return to that danger and those areas of risk, and many of them probably don’t want to be found, because they’re in hiding for their own safety.”

Beyond the logistical concerns of locating missing indigenous parents—whose access to telephones in remote areas can already be limited—there are very few organizations locally who are capable of tracking them down on behalf of the U.S. government or non-profits seeking to reunite them with their child.

“They are not going to trust an organization, much less their own government, to have access to them or find them,” Burgi-Palomino said. “The whole task of finding these parents and kids is going to be like finding a needle in a haystack.”