Eyewitness statements in the report detail "unprecedented" levels of violence, include burning people alive, raping girls as young as 11 and cutting children's throats.
UN High Commissioner for Human Rights Zeid Ra'ad Al Hussein said in a statement
the report indicates "very likely commission of crimes against humanity."
Aye Aye Soe, a spokeswoman for the Myanmar government, said the government has seen the report and is "very concerned about the allegations"
"The Investigation Commission headed by the Vice President will look into it. If evidences of the violations are found we will definitely take action on them," she told CNN via email.
Soe said she would respond to CNN with more details at a later date.
A United Nations team in Bangladesh interviewed about 220 Rohingya Muslims who had fled Rakhine State after the outbreak of violence
for the report.
There have been numerous allegations of human rights abuses
in Rakhine State in recent months, but CNN has been unable to verify them, due to the Myanmar government's tight travel restrictions.
The United Nations estimates about 69,000 people have fled from Myanmar to Bangladesh since the violence began.
Mother burned to death 'before my eyes'
Out of the 220 people interviewed, the report said 65% had witnessed killings, while just under half had personally had a family member murdered.
A woman from Kyet Yoe Pyin village alleged her 5-year-old daughter was killed when she tried to stop attackers from raping her mother.
"She was screaming, one of the men took out a long knife and killed her by slitting her throat," the report says.
A young girl told interviewers soldiers killed her father, then raped her mother before locking her inside the family's house and burning it down. "All this happened before my eyes," she said.
More than half of the 101 women interviewed by the UN reported either rape or sexual assault before fleeing Rakhine State -- the youngest was 11 years old.
Sixty-four percent of those interviewed reporting burning or destruction of property while 37% said their own property had been stolen or looted.
There were also allegations of torture, including beating and sexual humiliation.
Fleeting glimpses emerge
Up until now only fleeting glimpses of the situation inside the Rakhine State have emerged.
A Rohingya refugee who lost his 16-month-old son Mohammed
fleeing Myanmar told CNN they had left after the military attacked their village, burning his grandfather and grandmother alive.
"We couldn't stay in our house. We fled and went into hiding in the jungle," he said.
The Myanmar government has repeatedly denied claims of human rights abuses
, saying they are carrying out "clearance operations" against suspects who attacked Myanmar border guards in October 2016.
Myanmar's government is still limiting access for aid agencies and journalists to the area.
Former United Nations Secretary General Kofi Annan, who is part of a Myanmar-government commission into the Rakhine State, has said he is "deeply concerned" about the violence
Rohingya Muslims, a stateless minority recognized by neither Myanmar nor neighboring Bangladesh, have expressed their disappointment with State Councilor Aung San Suu Kyi
, who they'd hoped would help them after decades of discrimination.