yangon myanmar commit crimes humanity campaign muslim insurgents rakhine state human right watch say tuesday call u.n. security council impose sanction arm embargo u.n. refugee agency call redouble international aid 480,000 refugees 60 percent children flee bangladesh since aug. 25 escape violence myanmar government spokesman reject accusation crimes humanity say evidence u.s. government work hard establish close tie myanmar civilian government face competition strategic rival china comment directly human right watch charge however spokeswoman say closely monitor situation facts grind continue unfold deeply trouble report extrajudicial kill sexual violence burn rohingya villages security force non-rohingya individuals u.s. deputy secretary state john sullivan tell u.s. house foreign affairs committee u.s. ambassador myanmar would visit border rakhine look crisis within next two days myanmar leader aung san suu kyi invite foreign diplomats visit area speech last week myanmar also reject u.n. accusations force engage ethnic cleanse rohingya muslims response coordinate attack rohingya insurgents security force aug. 25. refugees arrive bangladesh accuse army buddhist vigilantes try drive rohingya buddhist-majority myanmar burmese military brutally expel rohingya northern rakhine state say jam ross legal policy director new york-based human right watch massacre villagers mass arson drive people home crimes humanity myanmar also know burma say force fight insurgents responsible attack police army kill civilians torch villages international criminal court define crimes humanity act include murder torture rape deportation commit part widespread systematic attack direct civilian population knowledge attack human right watch say research support satellite imagery find crimes deportation force population transfer murder rape u.n. security council concern countries impose target sanction arm embargo say government spokesman zaw htay say myanmar government ever commit promotion right current one accusations without strong evidence dangerous tell reuters make difficult government handle things coordinate group aid organizations say total number refugees flee bangladesh since aug. 25 revise 480,000 35,000 people two camp find miss previous tally massive influx people seek safety outpace capacities respond situation refugees still stabilize adrian edwards spokesman u.n. high commissioner refugees say geneva unhcr call redouble international humanitarian response bangladesh violence refugee exodus big crisis government nobel peace laureate suu kyi face since come power last year transition nearly 50 years military rule myanmar regard rohingya illegal immigrants bangladesh bouts suppression violence flare decades rohingya stateless suu kyi face scathing criticism call nobel prize withdraw denounce right violations address nation last week vow abusers would prosecute also say government try determine many people flee seven u.n. experts include yanghee lee special rapporteur right myanmar call suu kyi meet rohingya hear reason exodus one choose especially hundreds thousands leave home ancestral land matter poor condition flee strange land live plastic sheet dire circumstances except life-threatening situations say call myanmar provide humanitarian access rakhine state military restrict entry suu kyi little control security force military-drafted constitution also bar presidency give military veto power political reform myanmar see surge buddhist nationalism recent years public supportive campaign insurgents since sunday army unearth body 45 members myanmar small hindu community authorities say kill insurgents soon violence erupt arakan rohingya salvation army claim attack security force since october deny kill villagers hindus flee bangladesh others take refuge myanmar towns accuse insurgents attack suspicion government spy right group accuse myanmar crimes humanity