In the sprawling refugee camp that's sprung up in recent months to house hundreds of thousands of Rohingya refugees fleeing persecution and death in Myanmar, one of the busiest spots is an electronics repair shop.

"I use the term 'shop' pretty loosely. It's really just tarp underneath trees," reports CBS News' Adam Yamaguchi.

Inside that makeshift shop, technicians take apart and reassemble mobile phones that provide a lifeline for desperate refugees. The devices are ubiquitous in this muddy camp, just across the border in Bangladesh, where basic necessities like clean water and adequate food are in short supply.

"Everybody has a cellphone," Yamaguchi says. "This is how people get informed. This is how people communicate with family that have been strewn about many different camps -- some still across the border in Myanmar."

Electronics repairs in the refugee camp in Bangladesh. CBS News

The phones are also essential for Rohingya reporters and activists who use them to evade government censors and smuggle out news and video of the atrocities to the outside world, while international aid workers and journalists have been barred from the region and even arrested for trying to cover the crisis.

"We communicate through phone calls, and through WhatsApp and through WeChat, and through IM, and through Messenger, Facebook Messenger," said 30-year-old Ro Aung Zaw (a pseudonym he uses to protect his safety). He fled when his village was attacked and destroyed and is now part of a closely guarded network of about 20 members risking their lives to expose what U.N. officials say may amount to a genocide.

Rohingya Muslims make up a small minority of the population in the mostly Buddhist nation of Myanmar, formerly known as Burma. They have long faced discrimination and repression, and have largely been denied citizenship by the government, although many families have lived in villages concentrated in Myanmar's northern Rakhine state for generations.

After a Rohingya militant group attacked police posts and an army base in August, killing 12 security force members, the military responded with a campaign of indiscriminate violence against the Rohingya population. Troops burned homes and villages to the ground, killing thousands of men, women and children in tactics widely condemned as ethnic cleansing.

"The clearest evidence is, would be the satellite imagery that shows 340 destroyed villages. Not houses -- villages," said David Mathieson, an independent analyst who has lived and worked in the region for years.

Over the last six months, nearly 700,000 Rohingya have fled their homes, many with horrific memories of seeing loved ones slaughtered or of surviving gang rapes.

"The government's main plan is… to carry out slow and steady genocide and to wipe out this minority, clearly," said Ro Aung Zaw.

A Rohingya refugee child climbs stairs at Hakimpara refugee camp in Bangladesh on Jan. 27, 2018. More than half of the refugees are children, many of whom fled Myanmar alone. Getty

And yet, Mathieson notes, "the horrific violence that's driven at least hundreds of thousands of people into Bangladesh has been collectively overwhelmingly denied by so many people in Myanmar."

It's not just a campaign of silence -- it's one of systematic disinformation and persecution fueled by social media. In a tragic irony, some of the same digital tools the refugees consider a lifeline have been weaponized against them.

"Social media has been, I think, one of the most damaging aspects of this entire crisis," Mathieson said. "And I think people internationally need to realize that five years ago, it cost a couple hundred dollars to get a sim card. Not many people had phones. And so, what we've seen in the past three or four years is this country getting online, everyone having a cheap smartphone and access to Facebook. And so there's not the media literacy, there's not the kind of ability to understand this medium, and the limitations of online speech."

The number of Facebook users in Myanmar has skyrocketed from about 2 million in 2014 to more than 30 million today. The regime and its allies' views of events permeate users' news feeds -- and mindsets.

Facebook has now come under fire after reports said it mishandled data from more than 50 million users, allowing consulting firm Cambridge Analytica to access the data. Facebook has since suspended the firm -- that once worked for the 2016 Trump campaign -- for violating its privacy policy.

A whistleblower, Christopher Wylie, told CBS News that the data is a "political gold mine."

"If you're trying to influence an American election, that's a one stop shop," Wylie said.

The government, led by former dissident and Nobel Peace Prize laureate Aung San Suu Kyi, has promoted that message, reinforcing the widely-held belief that the Rohingya are not rightful citizens and downplaying abuses in the face of extensive evidence.

"I don't think there's ethnic cleansing going on. I think ethnic cleansing is too strong an expression to use for what's happening," Aung San Suu Kyi told BBC News.

Former pro-democracy activist and Nobel Peace Prize laureate Aung San Suu Kyi became leader of Myanmar in 2015. Getty

"What she has said has been really quite deplorable," Mathieson said. "She has denied the scale of this. She has questioned credible reports of really grave, serious crimes. ... It's contributed to dehumanizing the Rohingya, to whipping up ultra-nationalism and to degrading the relationship with the international community."

Since 2012, the country has seen an upsurge in extreme Buddhist nationalism. CBS News spoke with Ashin Sopaka*, a senior monk in the extreme Buddhist nationalist movement whose organization maintains an active Facebook presence.

"They call themselves Rohingya, but these Bengali people burn their own houses and they flee to another country. We did not burn their houses, as you see with the recent attack, they attacked the police posts," he said. "We will not give them any land. Not even one inch. They are people that want to kill people."

Yamaguchi observed, "When I go through Facebook, many of your prominent leaders and some of your biggest supporters post some of the most racist, vile, disgusting content I've ever seen online."

"Every person has their own opinion. That is their own feeling, but it is not representative of the organization," he replied.

On the streets of Yangon, Myanmar's largest city, those views are pervasive. Many perpetuate the false narrative of Rohingya as illegal immigrants from Bangladesh and repeat the claim that the Rohingya burned their own villages.

"Those people came over illegally from Bangladesh due to overpopulation," one man said. Another asserted, "Never accept a Rohingya in Myanmar."

Voices trying to counter that message include a punk rocker named Kyaw Kyaw, who says he faces virulent attacks online for supporting Rohingyas' rights.

"Technology is like a bomb in Myanmar. Right now everybody has a mobile phone. Everybody use social media, especially Facebook. They don't know how to respect the people. ... They don't know what is private or public. They need this education fast," he said.

Thet Swe Win, a Buddhist civil rights activist, is one of the few liberal voices in the country willing to speak out about the Rohingya, yet he feels he must be guarded with his words. At a recent human rights conference he avoided confronting the issue directly because of the hostility.

"This Rohingya case, it divided the people. I have seen many of the human rights defenders supporting the killing of the Rohingya people. They wrote it on Facebook: 'They should not be here, they're intruders, they're terrorists, kill them all.' It makes me not speak out as much as I want to those people," he said.

And he casts a wary eye toward the future.

"I'm very worried about my kids. They are very addicted to internet. They know how to use YouTube, Facebook, everything, you know? My daughter is just 4 and a half years old, and she knows everything."

Correction: This article has been updated to reflect that the quote is from Buddhist monk Ashin Sopaka, not Wirathu, the leader of his organization.