The person discovered by virtue of a search warrant is placed in police custody by the judicial police officer at the place of discovery, in accordance with the procedures set out in Article 154. The investigating judge hearing the case is informed of this as soon as police custody commences. Without prejudice to the possibility of the judicial police officer who has already received a letter rogatory to interview the person, the judicial police officer of the place where the person was discovered may be requested to do so by the investigating judge and to carry out any necessary investigative acts. During the period of police custody, the person may also be taken to the premises of the investigating department to which the facts were referred.