Tokyo police have arrested the principal of a public junior high school for allegedly possessing obscene images of an underage girl.

Kitamura Hisayoshi was arrested on Sunday on suspicion of violating a law banning child pornography. The 55-year-old heads a school in Tokyo's Nerima Ward. He allegedly possessed at his school office images of a girl under the age of 18.

The victim reportedly contacted the Tokyo Metropolitan Government's third-party consultation service last November. Police launched an investigation after it received word on the case through the local education board.

Kitamura has been quoted as saying that the images are those of a female student at a junior high school where he used to work.

Police searched the suspect's home and workplace, and reportedly found multiple obscene images and videos of Kitamura touching girls.

The superintendent of the Nerima Ward education board has offered deep apologies over the arrest of a top school official. The board says it will fully cooperate with the police investigation.

The junior high school held an assembly on Monday to brief and apologize to the students. It plans to conduct a survey of all students, and offer counselling to those who wish.