TOKYO, March 15, 2010 (AFP) - Japanese authorities have indicted the US head of an English school after finding 600 pornographic videos and photos he shot of his mostly elementary school age students, reports said Monday.

Investigators said the images found in a raid of his home in Fukuoka city indicated that the 69-year-old man had sexually abused more than 40 girls over the past decade, various media reports said without identifying the man. Police declined to immediately confirm or deny the reports.

The man, who was reportedly indicted for one abuse case, allegedly invited the girls to his house on the pretext of giving them "private lessons".

The man was first arrested in January on suspicion of committing lewd acts against his students but was not indicted at the time, Jiji Press news agency and other media reported.