At least 379,000 Rohingya refugees have entered Bangladesh since the latest spell of violence erupted in the Rakhine state, the International Organisation for Migration (IOM) has said.
IOM Asia-Pacific Spokesperson Chris Lom said these Rohingyas crossed the Bangladeshi border between August 25 and September 12.
The number will easily cross 400,000 if the unprecedented influx continues, he told a media briefing in Cox's Bazar on Wednesday night.
About 60% of the refugees are children
, according to Unicef Bangladesh.
Myanmar army's latest security operation targeting Rohingya Muslims has forced hundreds of thousands of Rohingyas to flee the country where they are denied citizenship and forced to live in apartheid-like conditions.
The UN has condemned the operation, calling it ethnic cleansing.
The latest influx of refugees comes on top of the more than 87,000 Rohingyas who fled to Bangladesh from October 2016 to July 2017.
Lom said the UN agencies and the government feared that as many as 100,000 more people
could cross over. He called the mass exodus unprecedented in terms of value and speed.
The IOM is trying to provide the Rohingya refugees with food, shelter, medical attention and other facilities while abiding by government rules, Lom added.
Various international donors were working alongside the IOM and UNHCR to help the refugees.