Myanmar said that it will not cooperate with a United Nations independent investigator into human rights in the country.
Yanghee Lee, UN special rapporteur announced on Wednesday that Myanmar will not grant her access to the country for the rest of her tenure.
She had been due to visit in January to assess human rights across Myanmar, including abuses against Rohingya Muslims in Rakhine State.
“This declaration of non-cooperation with my mandate can only be viewed as a strong indication that there must be something terribly awful happening in Rakhine, as well as in the rest of the country,” she said.
On Tuesday, Myanmar's military said a forensic investigation has begun after the discovery of 10 bodies in a mass grave in a village in troubled Rakhine state, where the country's security forces have carried out a brutal crackdown against the Rohingya.
Local officials said that they were investigating the 10 unidentified bodies found Monday near a cemetery in Inn Din village.
More than 630,000 Rohingya have fled to Bangladesh since security forces in neighboring Myanmar launched a violent crackdown against them on August 25, turning it into Asia's worst refugee crisis in decades.
The United Nations and the US accuse Myanmar's military of human rights violations against Rohingya in Rakhine, including killings, rapes and the burning of homes. The UN has condemned the violence as ethnic cleansing.
International aid group Doctors Without Borders said last week that it conducted a field survey that found at least 6,700 Rohingya Muslims were killed between August and September in the crackdown.
International rights groups blame the government and military for being unwilling to investigate possible wrongdoing by government officials and have urged the government to accept the assistance of international investigators.
"It's critical they (the government) accept the assistance of impartial, independent investigators and allow them to immediately travel to Inn Din to probe what happened and make a full report," said Phil Robertson, Deputy Director of Human Rights Watch's Asia Division.
The military said in a statement Monday that legal actions would be taken against the perpetrators.