A manager of a "juku" cram school was arrested Tuesday on suspicion of kidnapping a 7-year-old boy from Tokyo's Itabashi Ward as the first-grader was on his way to school.

Yoshikazu Ueno

The suspect -- identified as Yoshikazu Ueno, 38 -- allegedly abducted Yuta Seto and released him unharmed Monday afternoon, about eight hours after he was kidnapped and after his mother handed over a 5 million yen ransom to a motorcycle courier, police said.

Ueno is a resident of neighboring Nerima Ward and runs a cram school attended by Seto's 9-year-old sister, according to police.

He is suspected of calling the boy's mother, Miho, 34, about a dozen times and ordering her in one of the calls to hand over the ransom money to a motorcycle courier. His initial demand was for 50 million yen, but the mother said she could only arrange for 5 million yen.

Police said the ransom money, which had been delivered according to the kidnapper's instructions, was found in an envelope at a private post box in a building in Shinjuku and was recovered without incident.

Police had Ueno voluntarily appear for questioning late Monday night as he looked like the person in sketches drawn based on the boy's description of his abductor, as well as the fact that comments from the kidnapper during the phone calls mentioned the imported car owned by the family, indicating the culprit was familiar with the family.

"I needed money because I have debts totaling some 10 million yen, including housing loan repayments and borrowings from consumer lending firms," police quoted Ueno as confessing. He added that he had no accomplices.

When asked why he decided to release the child, Ueno said he began to feel sorry for the boy and his family after listening to him wail and hearing the mother's strung-out voice on the telephone, police said. He added that he gave up because he felt police may had already begun investigating the case, they added.

Ueno opened a cram school for elementary school children in September 2000 after his former employer, a nonbank moneylender, went bankrupt. But the number of students has been declining, and recently Yuta's sister was the only student left at the school.

Ueno's wife, who was also teaching at the cram school, reportedly knew Yuta's mother as she taught Japanese and math to the sister once a week.

"I heard from my wife that (the Setos) were wealthy, having two imported cars and such," he was quoted as saying. He added that he went to see Yuta's house and its neighborhood about four or five days before the incident.

Police said Ueno told them he used a prepaid mobile phone to contact the mother along with a device to mask the sound of his voice, adding that he later ditched the phone and the device.

He said the van is his own.

Although Ueno claimed to have made up his mind to commit the act about two weeks ago, police said they suspect the plan may have been devised as early as summer, since the prepaid phone and voice-changing device were bought sometime after August.

As for the private post box where the ransom was dropped off, Ueno said it was not rented solely for the purpose of collecting the ransom but that it was used as a delivery address for parcels.