The person released is believed to be Japanese broadcaster NHK’s Tehran bureau chief, Shinnosuke Kawashima.

A Japanese citizen has been released on bail in Iran, according to Japan’s top government spokesperson, months after their detention amid the country’s antigovernment protests.

The Embassy of Japan in Iran confirmed on Tuesday that “a Japanese national who was detained by Iranian authorities on January 20 was released on April 6 local time,” said government spokesman Minoru Kihara.

In February, United States-funded Radio Free Europe reported that public broadcaster NHK’s Tehran bureau chief, Shinnosuke Kawashima, had been arrested in Iran and transferred to a local prison. The person released on Tuesday is believed to be Shinnosuke.

The individual appeared to have no health issues, Kihara told a press briefing, without providing further details or revealing their identity or what charges they faced.

Japan’s Kyodo News reported that the individual is not allowed to leave Iran. The wire also reported that the person has been charged with security-related offences and is expected to stand trial.

At the time of the Japanese national’s arrest, NHK said “there is nothing we can answer at this stage” and that staff safety was a top priority.

The Committee to Protect Journalists (CPJ) in February quoted a source as saying that another NHK journalist had dealt with Iranian authorities. The broadcaster’s longtime videographer, Mehdi Mohammedi, had his passport confiscated along with his personal devices.

Another NHK staff member – whose identity CPJ said it was withholding for safety reasons – fled Iran in early February after being summoned several times, the journalist rights organisation said.

Last month, Iran released another Japanese citizen who was being held, and who also was not named, with Tokyo saying on March 22 that the person would return to Japan.

The Japanese national released on bail on Tuesday had been arrested shortly after demonstrations erupted over the high cost of living in Iran, triggered by the worsening economic situation following decades of US sanctions, which ultimately led to large antigovernment protests.

The rallies were held before the US and Israeli militaries began “Operation Epic Fury” on February 28 and killed Iran’s Supreme Leader Ayatollah Ali Khamenei, triggering the current regional war.

Japan and Iran have historically had relatively friendly relations. But more recently, close US ally Tokyo has drastically reduced its once-substantial imports of Iranian oil as part of international pressure over Tehran’s nuclear activities.

On Monday, Japanese Foreign Minister Toshimitsu Motegi and his Iranian counterpart, Abbas Araghchi, held a call to discuss the war.