The United Nations has described the details of an investigation into the killing of Rohingya Muslims in Myanmar as "alarming" and said it showed the need for a thorough probe into the violence in the country's Rakhine state.

"We're aware of this latest report, the details of which are very alarming. This once more attests to the need for a full and thorough investigation by the authorities of all violence in Rakhine State and attacks on the various communities there," UN spokesman Farhan Haq told reporters.

The investigation has also prompted a demand from the United States for a credible probe into the bloodshed in Rakhine State.

There have also been fresh calls for the release of two journalists who were arrested while working on the report.

The special report, published overnight by Reuters, lays out events leading up to the killing of ten Rohingya men from Inn Dinvillage in Rakhine state who were buried in a mass grave after being chopped to death or shot by Buddhist neighbours and soldiers.

"As with other, previous reports of mass graves, this report highlights the ongoing and urgent need for Burmese authorities to cooperate with an independent, credible investigation into allegations of atrocities in northern Rakhine," US State Department spokeswoman Heather Nauert said.

"Such an investigation would help provide a more comprehensive picture of what happened, clarify the identities of the victims, identify those responsible for human rights abuses and violations, and advance efforts for justice and accountability," she said.


The Reuters report drew on interviews with Buddhists who confessed to torching Rohingya homes, burying bodies and killing Muslims in what they said was a frenzy of violence triggered when Rohingya insurgents attacked security posts last August.

The account marked the first time soldiers and paramilitary police have been implicated by testimony from security personnel in arson and killings in the north of Rakhine state that the United Nations has said may amount to genocide.

In the story, Myanmar said its "clearance operation" is a legitimate response to attacks by insurgents.

Asked about the evidence Reuters had uncovered about the massacre, Myanmar government spokesman Zaw Htay said yesterday, before publication of the report: "We are not denying the allegations about violations of human rights. And we are not giving blanket denials."

If there was "strong and reliable primary evidence" of abuses, the government would investigate, he said.

There was no comment from the government following the publication of the report.

Nearly 690,000 Rohingya have fled their villages and crossed the border of western Myanmar into Bangladesh since August.

Human Rights Watch said Myanmar's military leaders should be held accountable in an international court for alleged crimes against the Rohingya population.

"As more evidence comes out about the pre-planning and intent of the Myanmar armed forces to wipe out Rohingya villages and their inhabitants, the international community ... needs to focus on how to hold the country's military leaders accountable," said HRW's deputy Asia director Phil Robertson.

Campaign group Fortify Rights also called for an independent investigation.

"The international community needs to stop stalling and do what's necessary to hold accountable those who are responsible before evidence is tainted or lost, memories fade, and more people suffer," said the group's chief executive Matthew Smith.

United Nations' Special Rapporteur on freedom of opinion and expression, David Kaye, said in a tweet: "During the reporting of this article, two Reuters journalists were arrested by Myanmar police. They remain held & must absolutely be released."

Yanghee Lee, the UN human rights investigator for Myanmar who has been barred from visiting the Rohingya areas, echoed that call and added in a tweet: "Independent & credible investigation needed to get to the bottom of the Inn Din massacre."

Police arrested two Reuters reporters, Wa Lone and Kyaw Soe Oo, on 12 December for allegedly obtaining confidential documents relating to Rakhine.

The pair have been accused of violating Myanmar's Official Secrets Act. They are in prison while a court decides if they should be charged under the colonial-era act.