Authorities in Myanmar detained an American journalist, an employee at a local English-language publication, at the Yangon airport shortly before boarding a flight back home, according to his employer on Tuesday.
Danny Fenster, 37, has been taken to prison, dpa news agency quoted his employer, Frontier Myanmar, as saying in a statement.
The charges against Fenster are unknown.
"We do not know why Danny was detained and have not been able to contact him since this morning. We are concerned for his well-being and call for his immediate release. Our priorities right now are to make sure he is safe and to provide him with whatever assistance he needs," the statement said.
Frontier Myanmar's chief, Thomas Kean told dpa news agency that Fenster had worked at the newpaper since August 2020 and that he had been on his way to the US for personal reasons.
The military leaders of Myanmar have cracked down hard on anyone they view as an opponent ever since grabbing power in February.
There have been reports of more than 5,400 detentions since the start of their rules, including of many journalists.
Many reporters have already fled the country, though foreign correspondents had been viewed as enjoying a degree of protection.
"This unlawful restriction of a foreign journalist's freedom of movement is the latest grave threat to press freedom in Myanmar," read a statement from the US-based Committee to Protect Journalists.