Massive, makeshift refugee camps are sprawling over farms and open land in southern Bangladesh as more than 420,000 Rohingya Muslims flee violent attacks in their predominantly Buddhist homeland of Myanmar.

In a matter of weeks, thousands of temporary shelters have been erected in the Bangladesh district of Cox's Bazar, according to new before and after satellite images released exclusively to The Associated Press.

"Tents have sprung up all over the area. It's a dramatic expansion," said Stephen Wood, a senior imagery analyst at Westminster, Colorado-based DigitalGlobe, which used high-resolution cameras in space to take photos of the camps for the AP.

The images were released shortly before a truck filled with aid for refugees in the camps veered off a road and fell into a ditch, killing at least nine aid workers. The crash occurred just hours after another aid shipment in Myanmar, also known as Burma, was attacked by a Buddhist mob. 

One photo showed a long traffic jam of cars going through the area, possibly relief workers on their way in, or government workers trying to install water or shelter systems.

The images offer an expansive view of what journalists, government agencies and aid groups have been seeing firsthand. Existing facilities are overwhelmed by streams of desperate families walking overland or clambering out of boats because they fear for their lives following attacks that some world leaders call ethnic cleansing.

No clean water, hygiene facilities

Until now, the assumption was that the size of existing refugee camps had doubled in the past few weeks. A Sept. 16 satellite image of just one camp, Kutupalong, shows it stretched about 3.9 square kilometres, about four times its former size.

The landscape continues to change, however. In recent days Bangladeshi officials have been ordering some refugees out of Kutupalong camp and into Balukhali camp, a few kilometres away. DigitalGlobe's imagery showed that Balukhali has expanded dramatically as well.

Bangladesh Sprawling Camps

Combination of satellite photos show the thousands of temporary shelters erected in the Kutupalong area of Cox's Bazar, Bangladesh. Refugee camps in Bangladesh have grown dramatically since Rohingya Muslims began fleeing violence last month in their nearby homeland of Myanmar. (DigitalGlobe/Associated Press)

The United Nations has airlifted in thousands of shelters. The large white plastic tarps, held up with metal tent poles, have no floors, but do offer respite from the rain. And there aren't nearly enough. Other arrivals build bamboo structures and buy thin plastic sheeting at local markets to stay out of the rain. Multiple families cluster under each of them, lacking food and cooking pots, blankets or even spare clothes.

The UN says that unlike formal refugee camps, these new sites lack drinking water, toilets, soap or buckets.

No end in sight

Many anticipated this crisis.

When Myanmar's civilian leader Aung San Suu Kyi's party was elected in 2016 after more than five decades of military rule, the political shift offered a short, tense window of peace. But that quickly ended as Suu Kyi, a former political prisoner and champion of human rights, has been unable or unwilling to protect Rohingya from violence.

Last year, military attacks set off by the killings of nine police officers at border posts prompted tens of thousands of Rohingya to flee into Bangladesh, and four new makeshift settlements formed. Security forces responded to another wave of insurgent attacks late last month with a sweeping crackdown that drove hundreds of thousands more Rohingya from their homes, which in many cases were burned.

Bangladesh Sprawling Camps

A satellite image shows the proximity of four refugee settlements around Cox's Bazar, Bangladesh. There are currently more than 420,000 Rohingya in the country, and witnesses say as many as 100,000 more still waiting to cross the border from Myanmar. (DigitalGlobe/Associated Press)

Rohingya arriving in Bangladesh this week have told the UN that more than 100,000 more people are still waiting to cross the border into Bangladesh.

The Trump administration has pledged $32 US million in humanitarian aid — food, medical care, water, sanitation and shelter. Of that, $28 million will go to the Bangladesh side and $4 million to Myanmar.

On Sept. 15, the Canadian government announced $2.55 million in emergency funding for UN agencies assisting Rohingya refugees in Bangladesh. The money is supposed to buttress programs providing therapeutic feeding for pregnant women and small children, clinical care and psychosocial counselling and emergency obstetrics and neonatal care, International Development Minister Marie-Claude Bibeau said at the time.

Danger for aid workers

The aid workers who died in the crash were helping shipments delivered from the International Committee of the Red Cross make their way to Rohingya families. ICRC spokeswoman Misada Saif said all of the nine people killed were Bangladeshi workers hired to distribute food packages.

Another aid shipment was attacked by a Buddhist mob in Rakhine state Wednesday night. Police said about 300 people threw rocks and Molotov cocktails at officers as the crowd tried to block Red Cross supplies from being loaded onto a boat. 

No injuries were reported and police detained eight of the attackers. The shipment was ultimately loaded and sent to northern Rakhine state.

Bangladesh Sprawling Camps

The white-topped tents are emergency shelters delivered by the UN. They have no floors and many are filled with multiple generations of families huddled together for reprieve from rain. (DigitalGlobe/Associated Press)

There's no indication that Myanmar's security forces plan to end their campaign. In a speech Wednesday, the country's top general praised security forces for their "gallant" efforts.

Min Aung Hlaing said that more than a century ago when the area was a British colony, Rohingya — whom he referred to as "Bengalis" — were allowed to settle without restrictions.

"Later, the Bengali population exploded and the aliens tried to seize the land of local ethnics," Min Aung Hlaing said, according to his office's Facebook page. He described repeated army efforts since Myanmar independence in 1948 to "to crush the mujahedeen insurgents," including in 2012 and last fall.

"Race cannot be swallowed by the ground, but only by another race," he said. "All must be loyal to the state in serving their duties, so that such cases will never happen again."