A junior high school student who admitted abducting and murdering a 4-year-old boy in Nagasaki last week said he chose his victim at random, investigative sources said Thursday.

The suspect, who under the Penal Code cannot be held criminally responsible because he is only 12 years old, was taken into custody Wednesday and transferred Thursday afternoon to the Nagasaki Family Court after his case was sent there from a child welfare center.

Shun Tanemoto is believed to have been pushed off the roof of an eight-floor parking garage on the night of July 1 after disappearing from an electronics store about 4 km away where he had gone with his parents. Tanemoto's naked, battered body was found in a pool of blood at around 9:45 a.m. the following day next to the parking structure.