YANGON, Myanmar (REPORT) — Newly revealed video of Myanmar police beating Rohingya Muslims in northern Rakhine state has weakened months of government claims that its forces have not committed abuses in the tense and isolated region it has largely closed off to foreigners since a deadly insurgent attack in October.

The footage has made it more difficult for the government to say at least some abuses are not happening, and sown doubts into its dismissals of more grievous allegations such as rape, arson and murder.

Authorities quickly verified the video and detained the officers who were seen beating and kicking residents in a large-scale roundup.

According to the office of Myanmar leader Aung San Suu Kyi, the clip was posted to social media Dec. 31 but recorded Nov. 5 in a village called Kotankauk in the north of Rakhine, a state in western Myanmar where most of Myanmar’s more than 1 million Rohingya live. It was apparently filmed by a police officer, who recorded the beating while looking impassively into the camera and smoking a cigarette.

Aye Aye Soe, a spokesperson for the foreign ministry, insisted the event “has to be an isolated case.”

“You cannot just look at one incident and think, that’s the whole thing that is happening.”

She said that if the government is presented with facts, it will respond in kind, but that “it’s sort of mixed up and confusing over there,” and many allegations are difficult to verify.

“Come back with something concrete, and we will give you back something concrete,” she said.

Most journalists and aid workers, however, have been blocked from the area of Rakhine where abuses have been alleged.

Myat Thu, a former political prisoner and chairman of the Yangon School of Political Science, said the incident “undermines the government position a lot.” Asked whether he thought the video represented an isolated case, he said sarcastically, “I will say there are so many ‘isolated incidents’ in Rakhine state.”

The police were taking part in a search for militants from a fledgling insurgent group that says it is fighting for the rights of the stateless Muslim minority, who lack Myanmar citizenship though Rohingya have lived in the country for generations.

The militants killed nine police officers and stole weapons from their posts Oct. 9 in northern Rakhine state, setting off a “clearance operation” that resulted in tens of thousands of Rohingya fleeing across the border to camps in Bangladesh. Rohingya and rights groups say dozens have been killed as part of the operation, and the displaced have shared horrific tales that officials have repeatedly characterized as fabrications.

Police in the video were responding to an alleged follow-up attack in early November that killed one officer.

The state-backed Global New Light of Myanmar published details about the video Monday, but the next day returned to casting doubt on abuse claims with an article headlined, “Fabricated Stories, Misleading Pictures About Rakhine Cause Global Criticism.”

While some patently false videos and photos have been disseminated, rights groups say there are many legitimate abuse claims that demand an independent, international investigation.

“I’d say this video throws a stick in the spokes,” Matthew Smith, executive director of the NGO Fortify Rights, said in an email.

Former U.N. Secretary-General Kofi Annan, who heads a government-appointed commission to suggest ways to resolve tensions between Rakhine’s Muslim and Buddhist communities, recently visited the area and met with Myanmar leaders. He expressed concern about reports of human rights abuses but did not comment on their credibility, saying, “We didn’t go there to investigate.” He called for aid agencies to be allowed in as soon as possible and said he hoped media would be granted access as well.