British Foreign Secretary Boris Johnson says the United Nations must supervise the return of Rohingya refugees to Myanmar because many are scared to come home on their own.

Johnson spoke to reporters Sunday after his meeting with Aung San Suu Kyi, de facto leader of the country formerly known as Burma

“I saw real apprehension both in camps in Bangladesh and amongst the remaining villagers,” Johnson said. “The Burmese authorities need to work very hard with international agencies to overcome the real alarm that people feel about coming back to Burma.”

A military crackdown on Myanmar’s Rohingya Muslim minority sent hundreds of thousands fleeing to refugee camps in neighboring Bangladesh. Those who stayed behind in their destroyed villages still fear for their lives.

Along with the refugee camps, Johnson toured some of those villages attacked by Burmese forces.

“I’ve seen nothing like it in my life. Hundreds and hundreds of villages torched. It’s absolutely clear that what is needed now is…some calm leadership working with the U.N. agencies to get these people back home.”

Myanmar’s Nobel Peace Prize winning leader Aung San Suu Kyi has a shaky power-sharing agreement with the powerful Burmese military. She and her image as a woman of democracy and peace have come under global criticism for her reluctance to speak out against the tough crackdown on the Rohingya.

Rohingya Muslims say they are a long-persecuted minority in Buddhist-majority Myanmar and are denied many basic rights and educational and job opportunities.

The latest action by the Burmese military and others came after Rohingya rebels attacked police stations and army posts last August.

U.S. Secretary of State Rex Tillerson has accused Myanmar authorities of “ethnic cleansing” – a charge they strongly deny even as they refuse to allow U.N. investigators into the affected region.