An appeals court in Seoul overturned a lower-court acquittal of a professor and fined her on Friday, finding her guilty of charges that she defamed victims of Japan's wartime sexual slavery with her book.

The Seoul High Court handed down a fine of 10 million won ($8,846) to Park Yu-ha, a Sejong University professor, who was charged with defaming sexual slavery victims, known as "comfort women," with her controversial book "Comfort Women of the Empire."

Victims and other critics claimed the book disputes the coerciveness of the "comfort women" system.

Friday's verdict overturned the lower court's decision in January that she is not guilty because academic freedom is a basic right guaranteed by the Constitution.

Historians estimate that more than 200,000 women, mostly from Korea, were forced to work in front-line brothels for Japanese soldiers during the war. Korea was under Japanese colonial rule from 1910 to 1945. The victims are euphemistically called "comfort women." (Yonhap)