BANGKOK -- Myanmar's security authorities detained a Japanese man on Saturday, a source among the authorities revealed to Nikkei.

The Japanese Embassy in Myanmar has told Nikkei it confirmed from Myanmar authorities that a Japanese man in his 20s is in detention. The embassy said it learned from a police chief that the man is in healthy condition and being treated politely.  A source at the embassy said it will continue to gather information and ask for his release.

The man's name is Toru Kubota, according to local media reports. Authorities arrested him in Yangon along with two Myanmar citizens who were participating in a protest Saturday afternoon against the 2021 coup by the Southeast Asian nation's military.

Kubota likely is in the country as a freelance documentary filmmaker, a friend of his told Nikkei. This friend said Kubota has reported from Myanmar in the past but usually makes films in Japan where he is based. Kubota has been reporting about Myanmar citizens in Japan protesting against the junta.