Geneva: Myanmar’s military carried out mass killings and gang rapes on Muslim Rohingya with ‘genocidal intent’ and the commander-in-chief and five generals should be prosecuted for orchestrating the gravest crimes under law, U.N. investigators said on Monday.

The civilian government led by Aung San Suu Kyi has allowed hate speech to thrive, destroyed documents and failed to protect minorities from crimes against humanity and war crimes by the army in Rakhine, Kachin and Shan states, they said in a report.

In doing so, it ’contributed to the commission of atrocity crimes’, the report said.

A year ago, government troops led a brutal crackdown in Myanmar’s Rakhine state in response to attacks by the Arakan Rohingya Salvation Army (ARSA) on 30 Myanmar police posts and a military base.

Some 700,000 Rohingya fled the crackdown and most are now living in refugee camps in neighboring Bangladesh.

The U.N. report said the military action, which included the scorching of villages, was ‘grossly disproportionate to actual security threats’.

The United Nations defines genocide as acts meant to destroy a national, ethnic, racial or religious group in whole or in part. Such a designation is rare under international law, but has been used in countries including Bosnia and Sudan and in the Islamic State campaign against the Yazidi communities in Iraq and Syria.

‘The crimes in Rakhine State, and the manner in which they were perpetrated, are similar in nature, gravity and scope to those that have allowed genocidal intent to be established in other contexts,’ said the U.N. Independent International Fact-Finding Mission on Myanmar.

In the final 20-page report, it said: ‘There is sufficient information to warrant the investigation and prosecution of senior officials in the Tatmadaw (army) chain of command, so that a competent court can determine their liability for genocide in relation to the situation in Rakhine state.’

The Myanmar government, which was sent an advance copy of the U.N. report in line with standard practice, has not commented.

Contacted by phone, Myanmar military spokesman Major General Tun Tun Nyi said he could not immediately comment.

The U.N. panel, led by former Indonesian attorney-general Marzuki Darusman, named the Myanmar army’s commander-in-chief, Senior General Min Aung Hlaing, and five other generals who should face justice.

They included Brigadier-General Aung Aung, commander of the 33rd Light Infantry Division, which oversaw operations in the coastal village of Inn Din where 10 Rohingya captive boys and men were killed.

Reuters was unable to contact Min Aung Hlaing or Aung Aung on Monday.

The massacre was uncovered by two Reuters journalists - Wa Lone, 32, and Kyaw Soe Oo, 28 - who were arrested as a result last December and are being tried on charges of violating the country’s Official Secrets Act. The court had been due to deliver its verdict on Monday, but at a brief hearing earlier the proceedings were postponed until Sept. 3.

In April, seven soldiers were sentenced to 10 years in prison with hard labor for participating in the massacre.

The report said Suu Kyi, a Nobel Peace Prize laureate, ‘has not used her de facto position as Head of Government, nor her moral authority, to stem or prevent the unfolding events, or seek alternative avenues to meet a responsibility to protect the civilian population’.

Suu Kyi’s spokesman, Zaw Htay, could not immediately be reached for comment on Monday.

The top U.N. human rights official Zeid Ra’ad al-Hussein has called the crackdown against the Rohingya a ‘textbook example of ethnic cleansing’.

Suu Kyi’s government has rejected most allegations of atrocities made against the security forces by refugees. It has built transit centers to receive Rohingya returnees to western Rakhine state, but U.N. aid agencies say that it is not yet safe for them to return.