More than 2,000 Rohingya have massed along Myanmar's coast this week after trekking from inland villages in Rakhine state to join the refugee exodus to Bangladesh.

They follow more than half a million fellow Rohingya who have emptied out of northern Rakhine in a single month, fleeing an army crackdown and communal violence the UN says amounts to "ethnic cleansing".

The journey to Bangladesh is fraught with danger for the stateless Muslim minority, who have faced decades of systematic oppression in mainly Buddhist Myanmar.

After fleeing burning villages they say were set alight by soldiers and Buddhist mobs, more than 100 Rohingya have drowned in the scramble to cross the Naf river that divides the two countries.

Scores have drowned while trying to cross the waters, while those who survive face new dangers as they cram into squalid refugee settlements where food and clean water are in short supply. 

A Rohingya Muslim refugee walks by night after crossing the border from Myanmar.

A Rohingya Muslim refugee carries his belongings as he walks with other people by night after crossing the border from Myanmar.

Rohingya refugees who just arrived under the cover of darkness by a wooden boat from Myanmar.

A Rohingya refugee woman holds children as they are arriving under the cover of darkness by a wooden boat from Myanmar at Shah Porir Dwip, in Teknaf.

Bangladeshi officials give money for daily food ration to Rohingya Muslim refugees after they cross the border from Myanmar.

A Bangladeshi official gives money for daily food ration to Rohingya Muslim refugees after they cross the border from Myanmar.

Rohingya Muslim refugee walks after crossing the border from Myanmar.

Rohingya Muslim refugees walk by night after crossing the border from Myanmar.

Rohingya Muslim refugees walk by night after crossing the border from Myanmar.

Rohingya refugee sisters, who just arrived under the cover of darkness by wooden boats from Myanmar, hug each other as they try to find their parents at Shah Porir Dwip.

Rohingya Muslim refugees walk to a camp for refugees after crossing the border from Myanmar, in Teknaf on September 29, 2017