Myanmar's military said on Friday six Rohingya Muslims killed and nine wounded in an aerial attack in the western state of Rakhine this week were affiliated with an armed rebel group.
The army-run Myawady newspaper said the villagers were "together with terrorists while the army was cracking down on the Arakan Army's terrorist activities" on Wednesday in the township of Buthidaung.
Rakhine state came to global attention in 2017, when the Myanmar army drove about 730,000 ethnic Rohingya across the border into neighbouring Bangladesh, following attacks by Rohingya insurgents on police posts.
The United Nations has accused the army of 'genocidal intent' in cracking down on the Muslim minority.
More recently, the military has been battling another armed group, the Arakan Army, which draws recruits mostly from the ethnic Rakhine population.
The men were collecting bamboo near the Sai Din waterfall when an army helicopter attacked, three villagers and a regional lawmaker told Reuters on Thursday.
"All of them were bamboo workers," said Soe Tun Oo, a fellow labourer.
Arakan Army spokesman Khin Thu Kha denied the dead and wounded men were members of the armed group, saying the military had attacked indiscriminately.
"They bombed everywhere, believing there were Arakan Army members in the jungle," he added.
Ten people are being treated at the Buthidaung public hospital, Kyaw Min Tun, a hospital official, said on Friday.
In a statement, the military said nine injured were taken to a military-run hospital for treatment.
But a military spokesman, Tun Tun Nyi, declined to comment on the discrepancy between the accounts.
In Geneva, a spokeswoman for the United Nations High Commissioner for Human Rights said the organisation was "deeply disturbed" by the escalating violence in Rakhine and condemned "what appear to be indiscriminate attacks and attacks directed at civilians".
Ravina Shamdasani said there were "credible reports of the killing of civilians, burning of houses, arbitrary arrests, abductions, indiscriminate fire in civilian areas, and damage to cultural property".
She cited sources on the ground as saying at least seven people were killed on Wednesday and that the attack was carried out in an area where thousands of Rohingya were taking shelter having fled earlier fighting.
"As the international community is taking steps towards accountability for the crimes committed against civilians in previous years, the Myanmar military is again carrying out attacks against its own civilians - attacks which may constitute war crimes," she said.
More than 20,000 people have been displaced by the violence across five townships in Rakhine state, she said, urging authorities to allow humanitarian relief for those affected.
The United States embassy in Myanmar said this week it was "deeply concerned about the harm to civilians of the ongoing conflict in Rakhine and Chin States between the Arakan Army and the Myanmar military."
"We call on all parties to renew their efforts to end the fighting and work toward a peaceful resolution of the conflict."