The mobile phone records of a 13-year-old boy who was found fatally stabbed last week along the Tama River in Kawasaki show the Line messaging app was used to contact a former schoolmate just around the time he was killed, it was learned Thursday.
Ryota Uemura, a first-year student at a Kawasaki junior high school, is estimated by police to have been killed at around 2 a.m. Friday. At around the same time, the former schoolmate received a "friends" request on Line from Uemura's phone, according to the schoolmate's mother.
Since the message arrived in the middle of the night, the schoolmate found it strange and now wonders if it was a prank by Uemura's killer, the mother said.
Uemura's phone has not been found, and Kawasaki police are investigating the details of his whereabouts on Feb. 19, the night before he was killed. He went out after having dinner that night with his mother at home.
Meanwhile, police have found a wooden stick covered with blood near the crime scene, leading them to suspect Uemura was first beaten with the stick before being stabbed with knives, NHK reported.
Uemura also sustained several bruises on his arms and legs, the public broadcaster reported, quoting police sources.
The cause of Uemura's death was hemorrhagic shock. A cutter blade was found on the riverbank stained with blood, and there was a pool of blood nearby. The body had multiple sharp stab wounds on the neck.