Police arrested three 16-year-olds -- two boys and one girl -- Saturday on suspicion of abandoning a corpse after one of the boys turned himself in late Friday and confessed to killing a friend and leaving his body in a thicket in Sayama, Saitama Prefecture.
Following the confession, police searched the area and found the body of Tomoyuki Oyama, 16, a second-year student at a local prefectural high school.
Police believe the three suspects beat and kicked Oyama to death in a park in Iruma in the prefecture last Saturday and abandoned his body in the thicket, some 200 meters away and inside the Sayama city limits.
The victim's mother notified police Monday that her son had not been home since the previous Saturday, when he received a phone call and left on his bicycle, police said.
The three suspects, whose names are being withheld under the Juvenile Law, include a boy who works as a part-time crystal grinder, a boy with no occupation and a high school girl, police said. The two boys were classmates of Oyama during junior high school.