''Chapter II Cooperation with the ICC, Section 3 Surrender of an Offender Sought for Surrender, etc., Subsection 1 Surrender of an Offender Sought for Surrender, (Detention of an Offender Sought for Surrender)
Article 21 (1) Upon receiving an order under the provisions of paragraph (1) of the preceding Article, the Superintending Prosecutor of the Tokyo High Public Prosecutors Office shall, except when the offender sought for surrender is being detained under a provisional detention permit or when his/her detention under a provisional detention permit has been suspended, cause a public prosecutor of the Tokyo High Public Prosecutors Office to detain the offender sought for surrender under a detention permit that has been issued in advance by a judge of the Tokyo High Court.
(2) The provisions of Article 5, paragraphs (2) and (3), and Articles 6 and 7 of the Act of Extradition shall apply mutatis mutandis to the detention of an offender sought for surrender under a detention permit set forth in the preceding paragraph. In this case, the phrase "the requesting country, the valid period of the permit" in Article 5, paragraph (3) of said Act shall be deemed to be replaced with "the valid period of the permit."
(c) A person being transported shall be detained in custody during the period of transit;