FUKUOKA--An American who runs an English conversation school in Fukuoka Prefecture has been arrested on suspicion of sexually molesting a primary school girl whom he taught, according to investigation sources.

The Fukuoka prefectural police suspect the 69-year-old man raped or molested more than 40 girls over the past decade, and plan to investigate whether he committed similar criminal offenses.

The man already had been arrested and indicted on a separate charge that he allegedly videotaped another girl as she was naked in violation of the anti-child pornography and prostitution law.

The sources said the man admitted to the allegation and told the police the girl had initiated the incident.

In January, the man was arrested on suspicion of performing an obscene act on another girl in violation of the Child Welfare Law, but his indictment was suspended.

During that investigation, investigators confiscated hundreds of videocassettes from the man. After the prefectural police analyzed the images, they came to suspect the man may have repeatedly sexually abused at least 40 girls. Most of the girls believed to have been victims were primary schoolers.

The police rearrested the man in February on a fresh charge that he had videotaped another girl in violation of the anti-child pornography law. He was indicted on the second charge earlier this month.

The man told the police he intended to present the images to the children when they were older as mementoes of their youth, the sources said.

The man is believed to have lured the girls into his home by telling them he would hold a lecture meeting there, where he allegedly abused them.

He is alleged to have stopped the girls speaking out by telling them that if they talked about the abuse, both he and their parents would be arrested, the sources said.