Members of Myanmar's Rohingya Muslim minority testified in person for the first time on Wednesday in Buenos Aires, as part of an Argentinian judicial investigation into alleged crimes by the Myanmar military, an activist told AFP.

The hearing, behind closed doors, was "a historic day for everyone in Burma," as Myanmar is also known, said Maung Tun Khin, president of the British-based Burmese Rohingya Organisation UK.

"Finally in-person hearings are taking place and strong evidence" is being produced in a court of law, he said.

He did not specify the identity nor the number of "survivors" who had testified, nor the facts concerned, for "security reasons."

The hearings of half a dozen people were expected to continue until June 13, according to a source familiar with the case.

In 2021, Argentina's justice system, responding to a complaint, announced it was opening an investigation into alleged crimes by Myanmar soldiers against the Rohingya, under the principle of universal jurisiction enshrined in the constitution.

That same year, six Rohingya women, living as refugees in Bangladesh, had participated in a virtual hearing before an Argentinian court, citing sexual assaults and the death of relatives as a result of regime repression.

"In-person hearings of survivors continue, very important evidence is being produced," said Maung Tun Khin.

Argentina's courts have in the past agreed to examine overseas cases under the principle of universal jurisdiction, in particular crimes committed under the fascist regime of Francisco Franco in Spain.

The principle makes it possible to prosecute the alleged perpetrators of some of the most serious crimes, regardless of their nationality or where the crimes were committed.

About 750,000 members of the Rohingya community fled to Bangladesh in 2017 from a crackdown by the Myanmar military, which is now the subject of separate proceedings before the International Criminal Court and for "acts of genocide" before the International Court of Justice.