Child rape cases in Burma have surged by 40 per cent this year, state media reported.

The rise highlights a growing problem for the country, also known as Myanmar, which is still grappling with a dark past of human rights abuses.

By the end of October, 380 child molestation cases had been reported — 150 more than in the same period in 2015, and accounting for half of all reported rapes nationwide.

Rights activists fear the numbers could be the tip of the iceberg, as a culture of silence and victim blaming means abuse often goes unreported.

"Most most of the time it is carried out by family members, neighbours, relatives or someone close to the victims' families," police major Khin Maung Thin from Mandalay, where cases have doubled, told AFP.

"Brothers abuse sisters and fathers abuse daughters," he said.

Poverty and weak laws mean Burmese children are particularly vulnerable to abuse, and many are sold into labour or forcibly recruited to fight in the country's borderlands.

In pictures: Burma protests against Rohingya Muslims Show all 5 1 /5 In pictures: Burma protests against Rohingya Muslims In pictures: Burma protests against Rohingya Muslims Burma Buddhist nationalists demonstrate against the UN and the return of Rohingya Muslims in Yangon In pictures: Burma protests against Rohingya Muslims Burma Hard-line Buddhist monks lead a demonstration against Rohingya migrants who were resettled in Rakhine state after being found at sea while fleeing Burma following anti-Muslim violence EPA In pictures: Burma protests against Rohingya Muslims Burma Buddhist monks demonstrate against the UN and the return of Rohingya Muslims in Yangon In pictures: Burma protests against Rohingya Muslims Burma Buddhist nationalists demonstrate against the UN and the return of Rohingya Muslims In pictures: Burma protests against Rohingya Muslims Burma Radical Buddhist nationalists protest the international pressure on Myanmar to accept the repatriation of persecuted Rohingya boat refugees

Activists say many more are at risk of exploitation either as domestic helpers for wealthy families or within their own communities.

UNICEF's Myanmar representative Bertrand Bainvel said sexual violence is the second most widespread form of child abuse in the country.

"Sometimes families are reluctant to report [cases] because of the taboo surrounding the issue," he said.

"They think they are protecting victims by not reporting."

Muslims protest against what they say is Burma's crackdown on ethnic Rohingya Muslims (Jorge Silva/Reuters)

Burma has been plagued by allegations of human rights abuses.

Earlier this week, the UN's rights agency warned Rohingya Muslims in the country may be the victims of crimes against humanity.

The army has been accused of gang rape, torture and murder by fleeing members of the long-persecuted minority, leading thousands of angry Muslims to take to the streets across Asia in protest.

Analysis of satellite images by Human Rights Watch found 1,250 houses and other structures in Rohingya villages have been burned down.

Myanmar police officers patrol along the border fence between Myanmar and Bangladesh in Maungdaw, Rakhine State, Myanmar, Friday, 14 October, 2016 (AP)

Burmese leader Aung San Suu Kyi recently vowed to work towards "peace and national reconciliation" but gave no specific details on how her government intends to resolve the violence and discrimination faced by the Rohingya.