Tatsuya Kato, former Seoul bureau chief for Japan's Sankei Shimbun, arrives at the Seoul Central District Prosecutors' Office in Seoul October 2, 2014. Reuters/Kyodo
SEOUL—South Korean prosecutors indicted a Japanese journalist late Wednesday on a charge of defaming President Park Geun-hye by citing rumors about her activities immediately after a deadly ferry sinking in April.
The Seoul Central District Prosecutor’s office said an Aug. 3 article written by Tatsuya Kato, then Seoul bureau chief for the Sankei Shimbun, was based on “false facts,” the Japanese newspaper and South Korean media reported. Mr. Kato has been questioned three times by prosecutors and barred from leaving the country but hasn’t been detained, according to the Sankei Shimbun. Both Mr. Kato and his lawyer couldn’t be reached to comment.
In his report, Mr. Kato noted a major South Korean newspaper, Chosun Ilbo, had reported that Ms. Park’s whereabouts during the first few hours after the ferry disaster in April were unclear. Mr. Kato also cited rumors among unnamed financial-industry sources that Ms. Park had a private meeting at the time.
South Korea’s presidential office protested the Sankei report and threatened what it called “grave action” against the newspaper. A spokeswoman for the presidential office declined to comment on the indictment of Mr. Kato or discuss what action the presidential office had taken or might take against the newspaper.
Presidential office officials say Ms. Park was within the presidential compound during the initial hours after the ferry sinking and receiving briefings on the incident. No action has been taken against South Korean media outlets over the reporting of Ms. Park’s whereabouts.
The Sankei article was published on the newspaper’s website but not in print editions. Mr. Kato has been indicted on a charge of online defamation, which carries a higher penalty than offline defamation, due to an assumed higher speed in dissemination. The maximum penalty for online defamation in South Korea is seven years in prison. Offline defamation carries a maximum sentence of five years in jail.
South Korea’s foreign minister criticized the article in a meeting with his Japanese counterpart in August. Relations between the two countries remain strained over lingering disputes tied to Japan’s wartime colonization of the Korean peninsula. The conservative Sankei Shimbun has been one of the strongest critics of South Korea’s demands for Japan to do more to atone for its wartime actions.
In a statement on the newspaper’s website, Sankei President Takamitsu Kumasaka said the indictment was a serious breach of the freedom of speech and called for it to be withdrawn. Mr. Kato has been reassigned to a role in Japan, according to the newspaper, but has been unable to take up the new position.
A Japanese Embassy official in Seoul said Tokyo had conveyed its concerns about the case to the South Korean government.
“The indictment without arrest is extremely regrettable. Our government is concerned about the situation from the viewpoint of freedom of the press as well as bilateral relations,” the official said, asking not to be identified.
Japan’s top government spokesman, Chief Cabinet Secretary Yoshihide Suga, said at a briefing in Tokyo that the indictment had shown South Korea is “far apart from international norms on press freedom.”
Asked about the case in Washington, State Department spokeswoman Jen Psaki said the U.S. supported freedom of speech and expression. “We have outlined in the past…our concerns about the law on the books in South Korea,” she said.
South Korea has a history of suppressing free speech under military rulers who controlled the country until the 1980s. It has since transitioned to democracy, but the U.S. is among those who have criticized South Korea’s National Security Law for being used to stifle critics of the government.
Reporters Without Borders, a press-freedom advocacy group, ranked South Korea 57th out of 180 countries in its press freedom index this year.
“It is completely normal for news media to ask questions about the actions of politicians, including the president,” Benjamin Ismaïl, the head of the Reporters Without Borders Asia desk, said last month after Mr. Kato was questioned by prosecutors.
Corrections & Amplifications
South Korea’s maximum penalty for defamation in a print publication is five years in jail. An earlier version of this article incorrectly stated that the maximum penalty is three years.
—Jeyup S. Kwaak in Seoul
and Toko Sekiguchi in Tokyo contributed to this article.
Write to Alastair Gale at alastair.gale@wsj.com