Ten visiting investigators questioned around 35 people who gave accounts of horrors they faced, including the raping of women, killing of children and burning of villages, a local official said.
Myanmar's investigators visited relief camps in southern Bangladesh on Monday where they questioned some of the thousands of Rohingya Muslims who have fled Myanmar to escape persecution, reports said.
The Rohingya refugees refused to show their faces to the ten visiting investigators, fearing reprisals when they return home, said magistrate Imrul Kayes, who accompanied the team.
Kayes said that the men and women talked from behind a curtain and gave accounts of horrors they faced, including the raping of women, killing of children and burning of villages.
About 35 people described their experiences to the investigators in Cox's Bazar district, he said. The investigators did not speak to the media.
Rohingya Muslims have been fleeing apartheid-like conditions in northwestern Myanmar, where they have been denied citizenship, since the early 1990s. There are now at least 300,000 who have crossed into Bangladesh, according to the Red Cross.
A UN report last month, based on interviews with refugees in Bangladesh, said that the Myanmar army and police had committed mass killings and gang rapes of Rohingya in a campaign last October that may amount to crimes against humanity and ethnic cleansing.
Last week, the European Union called on the UN to send an international fact-finding mission to Myanmar to investigate allegations of torture, rapes and executions by the military against the Rohingya Muslims.
Myanmar's government has rejected the allegations, but promised to investigate.
The 1.1 million Rohingya are loathed by many from the Buddhist majority in Myanmar, who insist they are illegal immigrants from Bangladesh, even though many have lived in the country for generations.
The UN has described the Rohingya as the most persecuted minority in the world.
On Monday, Philippine President Rodrigo Duterte met State Counsellor Aung San Suu Kyi in Myanmar's capital, Naypyitaw.
During the talks, Duterte promised $300,000 in humanitarian aid for Rakhine state, where communal conflict has displaced tens of thousands of people, mostly Muslims.
Cyclone season challenges
Meanwhile, the Red Cross on Monday said that Rohingya refugees are living in "extremely poor" conditions in Bangladesh and need better shelter as the country's cyclone season approaches.
"Most don't have access to regular medical services and they are not getting enough food or sufficient nutrition," said Azmat Ulla, Bangladesh Head of the International Federation of Red Cross and Red Crescent Societies (IFRC), in a statement.
"We need to scale up our support, particularly as there will be additional challenges ahead with the onset of the flood and cyclone season," the IFRC official said.