The Tokyo Family Court decided Thursday to institutionalize a 13-year-old girl for pushing a boy from an apartment building in Tokyo in June, saying she has trouble thinking rationally.

The judgment also allows an institution to keep her under lock and key for up to 180 days over two years for rehabilitation. The decision took effect Thursday, though the institution to which she will be sent was not immediately known.

While the girl has denied pushing the boy, the court rejected her claim, concluding, "It is evident she made him fall."