Over 6,700 Rohingya killed in a single month, Doctors Without Borders estimates
August-September estimate does not include hundreds of other deaths not attributed to violence
International aid group Doctors Without Borders said its field survey has found at least 6,700 Rohingya Muslims were killed between August and September in a crackdown by Myanmar's security forces.
According to MSF, the dead included at least 730 children younger than five.
More than 630,000 Rohingya Muslims have fled Buddhist-majority Myanmar into Bangladesh to escape what the United Nations has called "ethnic cleansing."
"The peak in deaths coincides with the launch of the latest 'clearance operations' by Myanmar security forces in the last week of August," MSF medical director Sidney Wong said in a statement.
She said the findings were staggering, both in terms of the numbers of people who reported a family member dead as a result of violence and the horrific ways in which they said they were killed or severely injured.
MSF said that among children below five years old, more than 59 per cent who were killed during that period were reportedly shot, 15 per cent were burnt to death in their homes, seven per cent were beaten to death and two per cent died due to land mine blasts.
Belief the toll is underestimated
Myanmar's Information Ministry has said 400 people died following attacks by a militant Rohingya group on police posts on Aug. 25. It said most of the 400 were "extremist terrorists" who died during military "clearance operations."
More than one million ethnic Rohingya Muslims have lived in Myanmar, also known as Burma, for generations. They have been stripped of their citizenship, denied almost all rights and labelled stateless.
Since the Myanmar's military conducted operations against the Rohingya in Rakhine state, the civilian government has barred most journalists, international observers and humanitarian aid workers from independently travelling to the region.
MSF said the number of deaths is likely to be an underestimation "as we have not surveyed all refugee resettlements in Bangladesh and because the surveys don't account for the families who never made it out of Myanmar."