Forty-two teachers filed appeals Friday with the Tokyo Metropolitan Government, demanding that the board of education retract the punishment meted out to them for refusing to stand and sing the national anthem during school commencement ceremonies.

The teachers, from metro government-run schools, are among 206 reprimanded between February and April for not singing "Kimigayo" or refusing to play the piano for the song. They claim the punishment violates their constitutional freedom of thought and conscience.

"I am very angry that my pay was cut for simply refusing to stand at the commencement," Atsuko Watanabe, teacher at a school for disabled children, told reporters Friday.

Separately, 75 of the 206 reprimanded teachers had filed similar appeals with the metro government on April 5.

In October the board of education advised principals of 347 metro public high schools and schools for disabled children to make sure all teachers rose and sang the anthem while facing the Hinomaru national flag hoisted at center stage.

The Hinomaru and "Kimigayo" ( unofficially translated as "His Majesty's Reign") were legally recognized as national symbols in a 1999 law. But their status remains a sensitive issue due to their links to Japan's Imperial system and militarist past.