geneva rohingya refugees flee myanmar testify consistent methodical pattern kill torture rape arson take place unite nations human right investigators say friday first mission bangladesh fact-finding team lead former indonesian attorney general marzuki darusman say death toll myanmar army crackdown follow rohingya insurgent attack aug. 25 unknown may turn extremely high hear many account people many different villages across northern rakhine state point consistent methodical pattern action result gross human right violations affect hundreds thousands people darusman say statement team three independent experts spend six days interview 600,000 rohingya myanmar northern rakhine state refugee camp near cox bazar advance team u.n. right officer conduct comprehensive interview weeks say deeply disturb end visit darusman say radhika coomaraswamy another member veteran u.n. human right investigator say leave shake angry testimonies account sexual violence hear victims horrendous hear long experience deal issue many crisis situations say one could see trauma eye women interview prove kind abuse must never allow go unpunished u.n. team establish u.n. human right council march renew appeal access rakhine state talk myanmar government military establish facts third member christopher sidoti say rohingyas must allow return rakhine wish mechanisms put place ensure safety may require placement international human right monitor rakhine state say 'consistent pattern crimes myanmar 's rohingya u.n. experts say