UN human rights experts investigating a possible genocide in Myanmar have said that Facebook had played a role in spreading hate speech against the majority-Muslim Rohingya minority.

The UN's Special Rapporteur on Myanmar also said that the Rohingya crisis in the Rakhine State "bears the hallmarks of genocide".

More than 650,000 Rohingya have fled Myanmar's Rakhine State into Bangladesh since a military crackdown last August. Many have provided harrowing testimonies of executions and rapes by Myanmar forces, but Myanmar's national security adviser demanded "clear evidence" for the potential acts of genocide.

Facebook role

Marzuki Darusman, chairman of the UN Independent International Fact-Finding Mission on Myanmar, told reporters that social media had played a "determining role" in Myanmar.

"It has ... substantively contributed to the level of acrimony and dissension and conflict, if you will, within the public. Hate speech is certainly, of course, a part of that. As far as the Myanmar situation is concerned, social media is Facebook, and Facebook is social media," he said.

UN Myanmar investigator Yanghee Lee said Facebook was a huge part of public, civil and private life, and the government used it to disseminate information to the public.

"Everything is done through Facebook in Myanmar," she told reporters, adding that Facebook had helped the impoverished country but had also been used to spread hate speech.

"It was used to convey public messages but we know that the ultranationalist Buddhists have their own Facebooks and are really inciting a lot of violence and a lot of hatred against the Rohingya or other ethnic minorities," she said.

"I'm afraid that Facebook has now turned into a beast, and not what it originally intended."

Yeehang Lee's comments follow the release of images by the human rights group Amnesty International.

Facebook response

Facebook said there is "no place for hate speech" on its platform.

"We take this incredibly seriously and have worked with experts in Myanmar for several years to develop safety resources and counter-speech campaigns," a Facebook spokesperson told the BBC.

"Of course, there is always more we can do and we will continue to work with local experts to help keep our community safe," Facebook spokesperson has said.