U.N. human rights experts investigating a possible genocide in Myanmar said on Monday that Facebook had played a role in spreading hate speech there.

Facebook had no immediate comment on the criticism on Monday, although in the past the company has said that it was working to remove hate speech in Myanmar and kick off people who shared such content consistently.

More than 650,000 Rohingya Muslims have fled Myanmar's Rakhine state into Bangladesh since insurgent attacks sparked a security crackdown last August. Many have provided harrowing testimonies of executions and rapes by Myanmar security forces.