(Reuters) - The United States will continue to hold accountable those responsible for what he described as the “abhorrent ethnic cleansing” of Rohingya Muslims in Myanmar, U.S. Secretary of State Mike Pompeo said on Saturday.

FILE PHOTO: U.S. Secretary of State Mike Pompeo speaks during a news conference at the ASEAN Foreign Ministers' Meeting in Singapore August 4, 2018. REUTERS/Edgar Su

Pompeo’s statement came on the one year anniversary of the conflict in western Myanmar’s Rakhine state that drove more than 700,000 Rohingya from their homes into neighboring Bangladesh.

“A year ago, following deadly militant attacks, security forces responded by launching abhorrent ethnic cleansing of ethnic #Rohingya in Burma,” Pompeo said on Twitter, using an alternative name for Myanmar.

“The U.S. will continue to hold those responsible accountable. The military must respect human rights for #Burma’s democracy to succeed.”

The military ruled Myanmar for nearly 50 years after seizing power in a 1962 coup and retains considerable powers under a 2008 constitution.

Myanmar government spokesmen Zaw Htay was unavailable for comment on Sunday.

The government, led by Nobel Peace laureate Aung San Suu Kyi, has denied refugees’ allegations of atrocities, saying security forces lawfully suppressed Muslim militants in Rakhine.

Rohingya refugees in Bangladesh held demonstrations and prayers on Saturday to mark the anniversary of the outbreak of the conflict.

Thousands of refugees marched prayed and chanted slogans in events across the sprawling camps in southern Bangladesh. Many wore black ribbons to commemorate what they said was the start of the “Rohingya genocide”.

Across the border in Myanmar, the government said security patrols had been increased in the conflict area ahead of the anniversary for fear of further violence. Members of the mostly Buddhist Rakhine ethnic group and Hindus from Rakhine state said they would hold events to remember those killed by Rohingya militants in attacks that triggered the crisis.

Earlier this month, the United States imposed sanctions on four Myanmar military and police commanders and two army units, accusing them of “ethnic cleansing” against Rohingya Muslims and widespread human rights abuses across the Southeast Asian nation.

International pressure on Myanmar has been growing as U.N.-mandated investigators are set to publish a report on the crisis on Monday and the United Nations Security Council will hold a briefing on Myanmar on Tuesday.