A 35-year-old man and his teenage wife were arrested Saturday for allegedly leaving two infant children unattended for 13 straight hours at their home in northern Japan, with the younger child later confirmed to have died, police said.

Mitsuhiro Abe and his wife are suspected of leaving a 2-year-old boy and his 4-month-old brother alone at the family home Wednesday in Kushiro, Hokkaido, from around 8:30 a.m. to 10 p.m. while they went to a pachinko parlor, the police said.

Photo taken on June 11, 2022, shows the home of Mitsuhiro Abe, who was arrested for leaving two infant children unattended in Kushiro, Hokkaido in northern Japan. (Kyodo)

The woman's name and age have not been released as she is a minor. Japan lowered the age of adulthood from 20 to 18 in April.

The younger brother was found unconscious and after being transported to a hospital confirmed to have died. The hospital reported the incident to police, authorities said.

Neither boy had obvious injuries and no previous health issues.

The police are investigating the cause of the younger boy's death and whether either child had been subjected to regular abuse.

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