A junior high school teacher who was fired in March plans to sue the Tokyo Metropolitan Government and its education board over what she is calling illegal punishment, sources familiar with the case said Wednesday.

The teacher, whose name has been withheld, was dismissed on March 31 from her position at a public school run by Tokyo's Chiyoda Ward for describing a member of the Tokyo Metropolitan Assembly and a history text publisher as "history distorters" last year, the sources said.

In a document she circulated in her civics classes in August last year, the teacher criticized the assembly member and a publisher who is associated with a group that promotes revisionist views on wartime history by writing: "It is a shame that they do not recognize Japan's war of aggression."

The document mentioned the Japanese Society for History Textbook Reform, a group that played a leading role in editing a history textbook that has drawn fire both at home and from China and South Korea for allegedly whitewashing Japan's past militarism and attempting to justify its invasions of other Asian countries.

The teacher was reprimanded over the document and underwent a retraining program from last September to March, but ended up being fired, the sources said.

The teacher believes remarks by the assembly member and the history textbook contradict the government's recognition of Japan's wartime aggression, and that telling her students about them was therefore not inappropriate.

The woman argues that the reprimand last August was an abuse of the education board's right to discipline teachers and that her dismissal is illegal.