Save the Children confirmed Tuesday that two of its staff were killed in a Christmas Eve massacre in eastern Myanmar blamed on junta troops who forced 35 people from their vehicles, killed them and burned their bodies in an incident that drew U.N. and U.S. condemnation.

Save the Children, a U.K.-based aid organization with 900 staff operating in Myanmar, had confirmed over the weekend that a car used by their group was found burned near Moso village in Kayah state. On Tuesday they said two aid workers, fathers of infant children, were among the massacre victims.

“It is with profound sadness that we are confirming today that two members of Save the Children’s staff were among at least 35 people, including women and children, who were killed on Friday 24th December in an attack by the Myanmar military in Kayah State, in the east of the country,” the charity said in a statement.

“The men were on their way back to their office after working on a humanitarian response in a nearby community when they were caught up in the attack. The military forced people from their cars, arrested some, killed many and burnt the bodies,” it added.

The men were not named for security reasons, said Save the Children.

The group has temporarily suspended operations in Kayah, Chin, and parts of Magway and Kayin, said Inger Ashing, chief executive of Save the Children.

“This news is absolutely horrifying. Violence against innocent civilians including aid workers is intolerable, and this senseless attack is a breach of International Humanitarian Law,” said Ashing, who called for an arms embargo on Myanmar and action by the U.N. Security Council and the Association of Southeast Asian Nations (ASEAN).

Members of the ethnic Karenni Nationalities Defense Force (KNDF), an armed group fighting the junta, told RFA’s Myanmar Service Monday that women and children were among those slaughtered along a highway near Moso village in Kayah’s Hpruso township.

On Tuesday, U.S. Secretary of State Antony J. Blinken condemned the attack and called for an end to the sale of arms and dual-use technology to the junta that took over the country in a coup on Feb. 1.

“We are alarmed by the military regime’s brutality across much of Burma, including most recently in Kayah and Karen States,” he said a statement.

“The targeting of innocent people and humanitarian actors is unacceptable, and the military’s widespread atrocities against the people of Burma underscore the urgency of holding its members accountable,” Blinken added.

The top U.S. diplomat’s remarks followed a statement of condemnation on Sunday from Martin Griffiths, the U.N. under-secretary-general for humanitarian affairs and emergency relief coordinator, who said he was “horrified” by the reports and demanded a probe into the attack.

“I condemn this grievous incident and all attacks against civilians throughout the country, which are prohibited under international humanitarian law,” he said in a statement.

“I call upon the authorities to immediately commence a thorough and transparent investigation into the incident so that perpetrators can be swiftly brought to justice,” said Griffiths.

Junta spokesman and Deputy Information Minister Zaw Min Tun said on Monday that an incident had occurred in the area involving people “killed in the crossfire” between the military and unidentified “gunmen.”

“Our security forces encountered seven vehicles in the area, so they asked the vehicles to stop, but they refused and started to drive away. When our forces opened fire with small arms, they fired back at us,” he said.

Myanmar, which has endured five decades of harsh military rule since its independence from Britain in 1948, was thrown into political crisis on Feb. 1 when the military seized power from the country’s democratically elected National League for Democracy (NLD) government.

In the more than 10 months since, the military has killed at least 1,377 civilians and arrested nearly 8,300 others, mostly during widespread peaceful protests of the junta. The military has also launched offensives against several armed ethnic groups and prodemocracy People’s Defense Force militias in the country’s remote border regions.

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