James Gomez, Amnestys regional director for Southeast Asia and the Pacific, said on Thursday that "this grisly admission is a sharp departure from the army's policy denial of any wrongdoing".
"However it is only the tip of the iceberg and warrants serious independent investigation into what other atrocities were committed amid the ethnic cleansing campaign that has forced out more than655,000 Rohingya Muslims from Rakhine state since August," Gomez added.
Gomez said it was "appalling that soldiers attempted to justify extrajudicial executions by saying they [soldiers] were needed as reinforcements elsewhere and did not know what to do with the men."
"Such behavior shows a contempt for human life which is simply beyond comprehension," he noted.
The condemnation comes after Myanmar's army on Wednesday nightposted an announcement admitting that security forces had a hand in killing members of the Rohingyacommunityand dumping their bodies in a mass grave.
The military confirmed that security forces took part in killing "Bengali terrorists" on September 2 in the coastal village of Inn Din in Rakhine state, using a pejorative term for Rohingya Muslims.
The statement posted on the Facebook page of military commander-in-chief Min Aung Hlaing said an internal investigation had found the 10 men had been thrown alive into a mass grave and stabbed by Buddhist villagers.
Villagers and members of the security forces have confessed that they committed murder, the army said.
The public admission of wrongdoing is the military's first since it launched "clearance operations" against Rohingya Muslism in August, in what the United Nations has called "ethnic cleansing".
On December 18, the military announced that a mass grave containing 10 bodies had been found in Inn Din, about 50 km (30 miles) north of the state capital Sittwe.
Rohingya Muslims who fled Inn Din to Bangladesh said Thursday that the victims were all civilians, not fighters as claimedby the army.
Inn Din villager Wal Marjan,at a refugee camp in southeast Bangladesh, said they were attacked by Buddhist mobs flanked by soldiers, who later "selected 10 to 15 men to attend a meeting".
They were never seen again, said Marjan, who was later told by another man that her husband and the others were slaughtered.
"He said his body was thrown into a mass grave with the other men," she said, stressing that her husband had no connections with Rohingya fighters.
[caption id="" align="alignnone" width="555"]
In a photo taken on November 28, 2017, Rohingya women and children gather to collect aid at the Kutupalong refugee camp in Bangladesh's Cox's Bazar. (Photo by AFP)[/caption]Hossain Ahammad, anotherInn Din villager,said the slain men were "fishermen, farmers, lumberjacks and clerics".
Since August 25 when Myanmar's military launched anew wave of violence,troops have been committing killings and rapes, making arbitrary arrests, and carrying out mass arson attacks to destroy houses in Rakhine.
Only in its first month, the clampdown killed some 6,700 Rohingya Muslims, including more than 700 children, according to the international medical charity Doctors Without Borders.
Myanmar brands more than one million Rohingya Muslims in the country as illegal immigrants from Bangladesh, refusing to accept them as citizens despite the fact that they have livedin the country for many generations.
The Rohingya are considered by the UN as the most persecuted minority group in the world.
