Reporters Without Borders (RSF) has called for the immediate and unconditional release of Danny Fenster, a US journalist who has been detained by Myanmar’s junta for the past 170 days and who is now facing two additional charges, including one – terrorism – that carries a possible life sentence.

The editor of Frontier Myanmar was told that the Yangon prosecutor’s office is also charging him with “sedition” under section 124a of the penal code, and “terrorism” under section 50a of the terrorism law, a charge punishable by imprisonment for life.

Arrested on 24 May as he was about to fly back to the United States to visit his family, Fenster was initially charged with endangering the interests of the armed forces under section 505a of the penal code, a charge used by the junta to imprison all journalists arrested by the military.

A second charge of illegal association was added to his indictment on 4 October, and a third charge of “illegal association” was brought against him a month later, on 3 November.

“With five charges, including one that could result in his spending the rest of his days in one of Myanmar’s prisons, the treatment reserved by the junta for Danny Fenster clearly constitutes persecution,” said Daniel Bastard, the head of RSF’s Asia-Pacific desk. “This journalist is paying a high price of his commitment to press freedom in Myanmar. We demand his immediate and unconditional release.”

A US State Department spokesperson said: “The regime should take the prudent step of releasing him now... His continued detention is unacceptable." The military junta did not comment on the new charges.