Police accused Mamahdnu Aka Aula of leading an attack on a police post near the border with Bangladesh in October, one of several attacks which prompted a brutal response from Myanmar's security forces which the United Nations says could amount to crimes against humanity.

Nine police officers were killed in the attacks which Myanmar authorities have claimed were backed by a Muslim extremist group based in Pakistan and Saudi Arabia.

The sentencing in a court in Rakhine's capital Sittwe comes as intentional pressure grows for an independent investigation into a UN report that documents mass rapes, murders, forced disappearances, beatings and families locked in torched houses and burnt alive.

A baby's throat was slit while he cried out for his mother's milk while she was being gang raped and soldiers stomped on the stomach of a pregnant woman while she was in labour.

For months Myanmar's government denied claims of atrocities by Rohingya who had fled the violence in Rakhine and arrived in squalid refugee camps in Bangladesh.

But after an international outcry over the UN report, including condemnation by Pope Francis, Myanmar's government on Monday set up a team of five high-ranking police officers to investigate.

The report was earlier referred to a government commission led by a retired general that was widely seen as a whitewash.

The Ministry of Home Affairs instructed the new team to follow "international standards" in accordance with the criminal code following a series of secret meetings between Myanmar's leader Aung San Suu Kyi and powerful military chief Min Aung Hlaing.

Nobel peace laureate Suu Kyi, who led her National League for Democracy to a landslide victory at historic elections in late 2015, appears to have had little sway over the country's military that controls key security ministries.

She has been widely criticised for failing to stand up for more than one million Rohingya in Rakhine who have been denied basic rights, including citizenship, despite the fact they have lived in the Buddhist majority country for generations.

Police say 13 other Rohingya men have been arrested and were awaiting sentencing in Sittwe on charges of intentional murder in relation to the police post attacks, the AFP newsagency reported.

The International Crisis Group has said the attackers were from a group called Harakah al-Yaqin, which had spent years recruiting and training fighters in Bangladesh and northern Rakhine.

Aparupa Bhattacherjee, who studies religious radicalism in south-east Asia at the National institute of Advanced Studies in Bangalore, said a new generation of Rohingya did not see any hope for any political or peaceful resolution to their plight in Rakhine and were "ready to fight for their rights".

Videos of the group posted on YouTube show mostly men in their 20s or younger.

Meanwhile, the Refugee Council of Australia has called on the Australian government to act to pressure Myanmar authorities to end the violence and ensure protection of the vulnerable.

"We should increase humanitarian assistance to those who had fled the crisis and ensure aid quickly reaches those who remain displaced and affected," said Paul Power, the council's chief executive officer.

"Australia has resettled just 37 Rohingya since 2013 and we should urgently increase the number of Rohingya who are resettled in our country as refugees," he said.