A 22-year-old student has been arrested on suspicion of selling compact discs from the United States containing pornographic images of children.

Police said Monday that they have turned over to prosecutors their case against Kei Nishida, who had been studying in Washington state, on suspicion of violating a law banning child prostitution. Police alleged Nishida sent a 25-year-old Osaka man a CD containing around 1,000 pornographic images of children that came from Canada after the man deposited 30,000 yen in the suspect's bank account in August.

It is the first time police have arrested a Japanese national who violated the law while living abroad. The law came into force in November 1999.

Nishida returned to Japan on Saturday after his father persuaded him to do so at the request of police.

The suspect told investigators he started marketing pornographic CDs via the Internet around spring to help pay for his living expenses in the U.S.

Police said Nishida's bank account records show more than 100 people in Japan purchased the CDs.