Police said Friday they have arrested a 15-year-old boy in connection with the stabbing of his grandparents in the city of Wako, Saitama Prefecture.

The third-year junior high school student, who lived at the same apartment building as his elderly relatives, is suspected of attempted murder of the 82-year-old grandmother. The grandfather, 87, was found dead with his wounded wife by their daughter, the boy's mother, at the condo on Thursday evening, police said.

The grandson disappeared after the incident but was taken into custody Friday morning near a train station in Kawagoe, Saitama Prefecture. Investigators said the boy has admitted to the charge.

The upper bodies of the couple sustained multiple cuts and stab wounds, while bloody clothes believed to be the boy's were found near the crime scene, according to police.

A security camera at the apartment had captured the teen walking in the direction of a train station.

The boy's 53-year-old mother went to check on her parents after being contacted by the grandmother.

At around the same time as the boy's mother reported the incident to police, they received eye-witness reports that a boy holding a knife was walking in the neighborhood. Local residents were alerted via community radio messages, and an athletic event at a local elementary school was canceled Friday.