* Myanmar army says cleared troops of nearly all alleged abuses
* Zeid says "ethnic cleansing is still underway"
* Zeid says alleged mass graves destroyed in bid to hide evidence (Adds response from Myanmar's army, quotes, detail)
By Stephanie Nebehay and Simon Lewis
GENEVA/YANGON, March 7 (Reuters) - The United Nations human rights chief said on Wednesday he strongly suspected that "acts of genocide" may have taken place against Muslim Rohingyas in Myanmar's northern Rakhine state since August.
His comments come as Myanmar's military published a lengthy response to widespread allegations over its campaign in Rakhine and said its investigations had cleared troops of almost all alleged abuses.
Zeid Ra'ad al-Hussein said in a speech to the U.N. Human Rights Council that reports of bulldozing of alleged mass graves showed a "deliberate attempt by the authorities to destroy evidence of potential international crimes, including possible crimes against humanity."
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 contexts including Bosnia, Sudan and an Islamic State campaign against the Yazidi communities in Iraq and Syria.
Zeid said last December that Myanmar's security forces may be guilty of committing genocide..
"This Council is aware that my office has strong suspicions that acts of genocide may have taken place in Rakhine State since August," he said, noting that his office said on Tuesday that it believes ethnic cleansing is still underway in Rakhine.
Nearly 700,000 Rohingya have fled Rakhine into Bangladesh since insurgent attacks sparked a security crackdown in August, joining 200,000 refugees from a previous exodus.
Rohingya are still fleeing because of "systematic" if lower-intensity persecution and violence there, Zeid said.
"Victims have reported killings, rape, torture and abductions by the security forces and local militia, as well as apparently deliberate attempts to force the Rohingya to leave the area through starvation, with officials blocking their access to crops and food supplies," he said.
The True News Information Team said in a Facebook post containing the army's position that the Arakan Rohingya Salvation Army (ARSA) armed group had "threatened, coerced and persuaded other villagers to flee to Bangladesh".
The post addressed a letter last month from British lawmakers to Foreign Secretary Boris Johnson calling for Myanmar to be referred to the International Criminal Court – which it said was based on "one-sided accusations" and ignored attacks on civilians by the ARSA - and a European Union decision to prepare sanctions targeted at Myanmar generals.
Zeid said his office had received reports of land inhabited by Rohingya being appropriated and members of other ethnic groups replacing them.
"A recent announcement that seven soldiers and three police officers will be brought to justice for the alleged extra-judicial killing of ten Rohingya men is grossly insufficient," he added.
Myanmar's government must take steps to provide real accountability for violations and respect the rights of Rohingya, including to citizenship, Zeid said.
A fact-finding mission set up by the Council, headed by former Indonesian Attorney-General Marzuki Darusman, is due to report on Monday on its initial findings based on interviews with victims and survivors in Bangladesh and other countries. (Writing by Stephanie Nebehay Editing by Tom Miles and Matthew Mpoke Bigg)
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