A South Korean appeals court on Friday overturned a lower-court acquittal of an author and found her guilty of defaming former "comfort women" in her book.

Park Yu Ha, a professor at Sejong University in Seoul, was also fined 10 million won (about $8,000) for citing false information in her 2013 book "Comfort Women of the Empire," thereby defaming the honor of the women forced into wartime brothels for the Japanese military.

The Seoul High Court decision followed a January acquittal of the Japanese literature scholar by the Seoul Eastern District Court on the grounds that freedom of expression is a basic right guaranteed by the constitution.

Park plans to appeal Friday's ruling to a higher court.

Prosecutors had sought a three-year prison term for Park. She was indicted in November 2015.

Park has been sued by a group of former comfort women for having disputed the coerciveness of the comfort women system and depicting some of them as "voluntary prostitutes."

Many comfort women were from the Korean Peninsula, which was under Japanese colonial rule from 1910 to 1945.