Save the Children says as more refugees from Myanmar arrive in Bangladesh, they face the risk of dying from a lack of food, water and supplies. One million Rohingya Muslims are expected to seek shelter by the end of the year.
Some 600,000 Rohingya children could flee to Bangladesh by the end of the year, a relief group said on Sunday, highlighting the scale of the humanitarian crisis triggered by violence in Myanmar's Rakhine state.
Around 409,000 Rohingya Muslims have now arrived in Bangladesh from their Buddhist-dominated homeland to escape violence that the United Nations says is a "textbook example of ethnic cleansing".
"That number could rise beyond one million by the end of the year if the influx continues, including about 600,000 children, according to UN agencies," Mark Pierce, the Bangladesh chief of Save the Children charity, said.
Kerry Alexandra has more.
According to the UN, more than half of the refugees are children, and more than 1,100 have arrived alone after trekking mud roads and hills for days.
The UN has also said it was possible that all the estimated 1.1 million Rohingya could flee Rakhine.
Rohingya refugees in Bangladesh could die due to a lack of food, shelter and water available for the huge numbers of them fleeing violence in Myanmar, Save the Children warned.
"Many people are arriving hungry, exhausted and with no food or water," Pierce said.
"I’m particularly worried that the demand for food, shelter, water and basic hygiene support is not being met due to the sheer number of people in need. If families can’t meet their basic needs, the suffering will get even worse and lives could be lost."
With food and water shortages already making life tough, torrential rain brought back swamp-like conditions to many parts of the border town of Cox's Bazar which has become a magnet for the Rohingya.
About 7.7 centimetres (three inches) of rain fell in 24 hours and more is predicted over the next two days, the Bangladesh Weather Department said.
Suu Kyi to address crisis
Aung San Suu Kyi is preparing to address Myanmar on the crisis for the first time – a high-wire act seeking to soothe global outrage without baiting an army that is again showing its teeth.
Suu Kyi took office last year as Myanmar's first civilian leader after 50 years of junta rule.
She has since focused her energy on the delicate political dance between her civilian government and the generals who still hold many of the levers of power.
Suu Kyi is due to make her first address to the nation on the crisis on Tuesday.
Her foreign supporters and Western governments that backed her campaign against military rule, and see her as the best hope for Myanmar's future, will be hoping to see her make a commitment to protect the rights of the Muslim minority.
Suu Kyi's supporters at home could be disappointed if she is perceived to be caving into foreign pressure and taking the side of a Muslim minority blamed for initiating the violence.