One aid worker, Caroline Vandenabeele, had seen the warning signs before. She worked in Rwanda in the run-up to the genocide in late 1993 and early 1994 and says when she first arrived in Myanmar she noticed worrying similarities.
"I was with a group of expats and Burmese business people talking about Rakhine and Rohingya and one of the Burmese people just said 'we should kill them all as if they are just dogs'. For me, this level of dehumanisation of humans is one sign that you have reached a level of acceptance in society that this is normal."