Rohingya refugees describe Myanmar’s military as beating, sexually assaulting and shooting villagers, including children. (Ismail Ferdous/Bloomberg News)

More than half a million Rohingya have arrived in Bangladesh from Myanmar since late August, escaping what U.N. officials have described as a classic case of ethnic cleansing.

Myanmar’s army launched comprehensive attacks on Rohingya villages in the country’s Rakhine state after the Arakan Rohingya Salvation Army (ARSA) — a Rohingya militant group — attacked Myanmar’s police. The country’s 1.1 million Rohingya Muslims are essentially stateless. Their government claims they are illegal immigrants from Bangladesh, but many Rohingya say they have lived in Myanmar for generations. Accounts of their origin vary — some historians trace them back to 15th century Arab, Turkish, or Mongol migrants, while others claim they have come from Bangladesh in phases. The Rohingya lack freedom of movement and access to basic services, such as health care, education and employment. Myanmar’s 1982 nationality law does not recognize them among Burmese ethnic groups.

Around 300,000 to 500,000 Rohingya refugees already lived in Bangladeshi camps before the current wave of refugees. The more recent arrivals describe Myanmar’s military as beating, sexually assaulting and shooting villagers, including children. Many Rohingya villages have been burned to the ground.

The Bangladesh government has responded to this crisis in partnership with national and international development agencies. But it’s not enough. The Rohingya crisis could still become into a massive humanitarian catastrophe. Here is why:

1. Humanitarian agencies can barely keep up with half a million incoming refugees.

Keeping people alive and healthy requires, at a bare minimum, enough shelter, food and water, medical assistance and toilets. Getting that many resources into place quickly is extremely challenging.

Already, as many as 14,000 children are suffering from severe acute malnutrition. The injured — including victims of sexual assault — need medical and counseling services. More than 18,000 of the new arrivals are pregnant; 150 have given birth in Bangladesh after walking for days. Monsoons have left some camps knee-deep in mud. A lack of toilets increases the risk of deadly communicable diseases. There’s just one hospital, which is working with health complexes, community clinics, nongovernmental organizations and international development agencies to deliver medical services around the clock. But it doesn’t seem to be enough.

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2. It is almost impossible to keep families together and safe.

An estimated 60 percent of the refugees are children, many separated from their families and possibly orphaned. They are sick, hungry and traumatized. Volunteers have been setting up booths to unite families; UNICEF is helping children overcome their trauma by drawing pictures. No law enforcement mechanisms are in place to prevent and address crimes within the camps themselves, including sexual violence and trafficking. Earlier this year, a number of children disappeared from Rohingya camps in Cox’s Bazaar, and NGOs working in these camps fear they were abducted and trafficked.

3. The refugee camps are too small.

Incoming refugees are being housed in 2,000 acres of cleared forest land in Cox’s Bazaar as well as additional makeshift camps spread out across the area. This is not enough space. It is also an area with complicated land politics of its own. Cox’s Bazaar lies close to the Chittagong Hill Tracts, which houses indigenous communities that have long been fighting the Bangladesh government. Although CHT peace accords were signed in 1997, they have been ineffective in stabilizing the region. Local indigenous groups regularly report land grabbing, forced displacement, communal conflicts and human rights abuses. Where necessary, land allocation must therefore consider both national and indigenous laws. What’s more, the presence of Rohingya refugees may cause tensions between the Bengali and indigenous communities to flare up into violence.

4. Despite Bangladesh’s efforts, this crisis is on an unprecedented scale.

The Bangladesh government is leading relief operations, which U.N. officials have praised. For a country with a history of instability, violence and corruption, the official response has been swift. The government has a history of remarkable development programming. The army has been helping the civil administration coordinate efforts. Some observers may be concerned about bringing in the army in a country with a history of military coups, but the army is actually part of the country’s national disaster strategy and has experience in humanitarian work and U.N. peacekeeping operations.

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But Bangladesh has never experienced a humanitarian crisis of such a massive scale. The influx may actually increase, outpacing all efforts.

5. Geopolitics complicates things.

The Bangladesh government has responded to the Rohingya on two fronts: first, with a humanitarian response; and second, through encouraging the Myanmar government to stop the persecution of the Rohingya in Myanmar.

But regional powers China and India are both backing Myanmar. India is trying to deport the 40,000 Rohingya currently living in the country, claiming that the refugees have terrorist ties. ARSA — who say that they are fighting for self-defense and citizenship — cannot match the Myanmar army. There is little evidence that the group can carry out mass operations. Despite some allegations of transnational connections, its members claim to have no links with international groups.

After much pressure from the international community, Myanmar has finally agreed to take back the Rohingya from Bangladesh. But repatriation may return the refugees to the same situation they escaped.

Nayma Qayum is an assistant professor in the Asian studies department at Manhattanville College in New York.