A couple in Tokyo was arrested Monday on suspicion of pouring scalding water four years ago over an 11-year-old boy who was living with them at the time, police said.

The boy suffered burns to his abdomen, back and feet that required three months' treatment.

Hiroaki Chubachi, 34, and his wife Ayako, 28, are suspected of pouring the scalding water over the boy at their home in Tokyo's Adachi Ward in mid-August 2015. They have admitted to the charge, they said.

The boy and his mother lived with the couple from 2012 after the mother met the Chubachis through religious activities.

In October 2016, the mother reported to the police that her son had been physically abused by the couple. But the boy refused to say how he suffered the burns. He recently broke his silence, however, leading to the arrest of the couple, investigators said.

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