The office of the United Nations High Comissioner for Refugees is monitoring developments after several thousand people living in a makeshift camp "were reportedly ordered to vacate the area by the Myanmar authorities", the agency said.
"It appears that widespread and systematic violence against the Rohingya persists", said Gilmour, stating that the violence had now shifted from "the frenzied blood-letting and mass rape of past year to a lower intensity campaign of terror and forced starvation that seems to be created to drive the remaining Rohingya from their homes and into Bangladesh".
Myanmar's government must take steps to provide real accountability for violations and respect the rights of Rohingya, including to citizenship, Zeid said.
A Rakhine leader facing treason charges linked to deadly riots appeared in a Myanmar court on Wednesday, a case that has aggravated ethnic tensions in Rakhine State.
The deadly riots exposed the bitter and complex ethnic fault-lines in Rakhine , where some 700,000 Rohingya Muslims based further north have fled over the border into Bangladesh since a brutal military campaign began in August.
Myanmar and Bangladesh have agreed to repatriate the Rohingya refugees within two years but most human rights advocates say it is unsafe now to send back the refugees.
"We have been told by Rohingya who fled from the no man's land that the security forces have been threatening them by shooting guns in the air, throwing stones at them and shouting at them to get out of the area", said Ko Ko Lin, a Rohingya activist in Bangladesh.
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The Russian mission to the United Nations in Geneva did not immediately respond to the findings. The goal of the operation is clear Turkey's Syrian border from the terrorist threat.
Myanmar's military claims its crackdown on Rohingya villages is aimed at eradicating "terrorists", who allegedly attacked border police posts in August 2017.
Refugees living in camps in southeastern Bangladesh have also resisted the idea, fearing they will not be safe if they return to Rakhine.
James Gomez, Amnesty International's director for Southeast Asia and the Pacific, said the UN's new findings "sadly echo our own".
"We don't drive out the refugees", he said.
Doctors Without Borders (MSF) has estimated that at least 6,700 Rohingya were killed in the first month of the crackdown alone.
"It appears that widespread and systematic violence against the Rohingya persists", Gilmour said.
Myanmar's civilian government, led by former democracy activist Aung San Suu Kyi, lacks control over the military but has been castigated by rights groups for failing to speak out in defence of the Rohingya.