Myanmar's government said eight people died and 36 were arrested in the latest clashes between the Myanmar army and what the government claimed are Rohingya militants.

Human rights groups accuse the military of killing, raping and burning the homes of Rohingya, a minority of almost one million people in Buddhist majority Myanmar.

New York-based Human Rights Watch said it had identified a total of 430 destroyed buildings in three districts of Maungdaw from an analysis of high-definition satellite imagery recorded between October 22 and November 10.

Brad Adams, the organisation's Asia director, said the images show the destruction is far greater than was at first thought and called on Myanmar authorities to promptly establish a UN-assisted investigation as a first step towards ensuring justice and security for the victims.

Myanmar's Information Ministry said the violence flared last weekend when government troops were ambushed by about 60 attackers armed with guns, knives and spears.

Two soldiers were killed in a subsequent battle involving 500 armed men, the ministry said, adding that two helicopter gunships joined the fight.

The military has imposed a lock-down on most of the region since October 9 when gunmen attacked three police posts near the border with Bangladesh, leaving nine policemen dead.

The government claims the attackers were Rohingya extremists but the actual responsibility remains unclear, human rights groups say.

Aid organisations, the United Nations, independent observers and the media have been prevented from going to the affected areas where tens of thousands of people have been forced from their homes.

The UN Children's Fund (UNICEF) said children there already suffer from high levels of deprivation and malnutrition.

"Their futures depend on help from doctors, nurses, teachers and others who can provide them with nutrition, health and education services," UNICEF said.

The violence is the most serious to hit to Rakhine since hundreds were killed in communal clashes in 2012.

More than 100,000 Rohingya are still living in squalid camps after being driven from their homes where they are denied citizenship and other basic rights, despite the fact their families have lived in the country also known as Burma for generations.

The United Nations has called on Myanmar to investigate reports of dozens of sexual assaults in Rakhine and to allow humanitarian assistance to reach the area to provide support for survivors.

Myanmar's National League for Democracy, led by Nobel laureate Aung San Suu Kyi, was swept into office in November 2015 promising to bring peace to the country's many ethnic minorities who account for up to 40 per cent of the country's population.

But wars in the north against Kachin, Shan and other ethnic rebel forces are continuing unabated despite peace talks in August.

More than 100,000 people have been displaced in the north as the military advances supported by helicopter gunships, jets and heavy artillery.

Ms Suu Kyi has been criticised for failing to speak up for the Rohingya as she is seen to be playing a delicate balancing act between her supporters and the military which kept her under house arrest for a total of 15 years.

Myanmar expert Bertil Lintner said a year after dancing in the streets to celebrate Ms Suu Kyi's victory a bitter reality has set in as she finds it was much easier to be the heroine of democracy than to rule a country torn apart by decades of civil war and ethnic and political strife. .

"And the military remains in the driving seat, despite the country having a civilian government for the first time since the early 1960s," he said.