A 32-year-old man was arrested Thursday in connection with the death of his 9-year-old stepson, a day after the child's body was found in an apartment building where they lived in Saitama, near Tokyo, police said.

Yusuke Shindo has admitted to murdering the boy and told police he hid the body after killing him, investigative sources said.

The body of Ryosuke Shindo, bearing marks of strangulation, was found before 1 a.m. Wednesday in a utility meter box opposite the family's apartment, after his 42-year-old mother, a teacher, reported him missing Tuesday evening, according to the police.

Shindo was arrested on suspicion of abandoning the child's body in the meter box.

The unemployed stepfather told the mother that evening the boy had gone to an English conversation school, but the child did not return home at the expected time. The police have since launched a murder investigation and determined the boy never arrived at the school.

The body was found clothed in a T-shirt and shorts but without shoes. An autopsy found that he died of suffocation.

The boy loved learning English and attended a class once a week, according to a teacher. The day before his body was found, the boy failed for the first time to come to the English school that he had been attending since April.

The mother of one of his classmates said she was surprised to hear the man had been arrested, adding the meter box was often used by children playing hide-and-seek.

"I feel nothing but sympathy for the mother," the 40-year-old woman said.

The apartment complex is a housing facility for teachers located about 4 kilometers east of JR Omiya Station.

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