A Christian charity is calling on the international community to take urgent action after reports of at least 35 civilians being burnt alive in Myanmar on Christmas Eve.
Christian Solidarity Worldwide (CSW) said the atrocity was carried out by the Tatmadaw - the Myanmar army - in Kayah State.
The victims include elderly people and children.
Their bodies were discovered by the Karenni Human Rights Group (KHRG) on Christmas Day.
CSW has also received reports of people being used as human shields and landmines being placed around villages.
The massacre is the latest in a string of violent attacks in Kayah State that have left over 600 homes, six churches and at least one clinic destroyed between May and December.
Dr Sasa, spokesperson of the National Unity Government of Myanmar and Myanmar Special Envoy to the United Nations, condemned the recent killings in the "strongest possible terms".
He said in a statement: "These acts clearly constitute the worst crimes against humanity and we expect that all peoples and governments the world over should condemn these acts.
"With the condemnation, however, should come a commitment that these criminals be brought to justice and held fully accountable for their actions."
Benedict Rogers, CSW's Senior Analyst for East Asia, is calling for a global arms embargo.
"As many of us celebrate Christmas, the Tatmadaw has continued to perpetrate egregious violations against the people of Myanmar, burning innocent civilians alive and killing and displacing hundreds more in targeted attacks on the country's ethnic and religious nationalities," he said.
"We call once again for urgent international action, and specifically for the swift and comprehensive imposition of a global arms embargo on the country as a means of pressuring the military regime to bring an end to these horrific atrocities."