Human Rights Watch on Tuesday accused the Myanmar army of burning hundreds of houses in the Rohingya Muslim minority villages where a massive military offensive has been ongoing for over two months.
The rights group, with the help of satellite images, said 1,500 houses were burnt by the army in the northern Rakhine state, EFE news reported.
The army's offensive followed an attack on October 9 against police border posts, allegedly by Rohingya insurgents.
The group said the pattern of torching houses coincided with the advance of the soldiers and their deployment in the villages.
The torching in three cases took place after alleged attacks by insurgents and suggests "a reprisal element", the report said.
It included the testimony of 10 Rohingya refugees, who fled towards Bangladesh due to the violence and witnessed soldiers setting houses on fire.
The report strengthens claims by local activists who accuse the army of carrying out killings, rapes and looting in the area which has been closed off to humanitarian aid organisations, observers and the media.
According to the UN, around 150,000 people were dependent on humanitarian aid for food and money before the armed attacks and subsequent military operation by the army, which has prompted at least 21,000 Rohingyas to flee to Bangladesh.
Both the army and the government denied the accusations and instead blamed the attacks on Rohingya militants.
HRW also urged the Myanmar authorities to open up the affected region to humanitarian aid and observers, following similar pleas by the UN and 14 diplomatic missions in the country in recent days.
Rakhine is home to more than a million Rohingyas, a community not recognised as citizens in the country and often shunned as Bangladeshi immigrants.
Around 120,000 of them live severely restricted lives in 67 camps since the outbreak of sectarian violence in 2012 when at least 160 people died.
The sectarian conflict in Rakhine is one of the main challenges facing the Aung San Suu Kyi administration, the first democratic one in the country in over half a century.