2. Each Contracting State shall likewise take such measures as may be necessary to establish its jurisdiction over the offence in the case where the alleged offender is present in its territory and it does not extradite him pursuant to Article 8 to any of the States mentioned in paragraph 1 of this Article.
3. This Convention does not exclude any criminal jurisdiction exercised in accordance with national law.
Article 5
The Contracting States which establish joint air transport operating organizations or international operating agencies, which operate aircraft which are subject to joint or international registration shall, by appropriate means, designate for each aircraft the State among them which shall exercise the jurisdiction and have the attributes of the State of registration for the purpose of this Convention and shall give notice thereof to the International Civil Aviation Organization which shall communicate the notice to all States Parties to this Convention.
Article 6
1. Upon being satisfied that the circumstances so warrant, any Contracting State in the territory of which the offender or the alleged offender is present, shall take him into custody or take other measures to ensure his presence. The custody and other measures shall be as provided in the law of that State but may only be continued for such time as is necessary to enable any criminal or extradition proceedings to be instituted.
2. Such State shall immediately make a preliminary enquiry into the facts.
3. Any person in custody pursuant to paragraph 1 of this Article shall be assisted in communicating immediately with the nearest appropriate representative of the State of which he is a national.
4. When a State, pursuant to this Article, has taken a person into custody, it shall immediately notify the State of registration of the aircraft, the State mentioned in Article 4, paragraph 1(c), the State of nationality of the detained person and, if it considers it advisable, any other interested States of the fact that such person is in custody and of the circumstances which warrant his detention. The State which makes the preliminary enquiry contemplated in paragraph 2 of this Article shall promptly report its findings to the said States and shall indicate whether it intends to exercise jurisdiction.
Article 7
The Contracting State in the territory of which the alleged offender is found shall, if it does not extradite him, be obliged, without exception whatsoever and whether or not the offence was committed in its territory, to submit the case to its competent authorities for the purpose of prosecution. Those authorities shall take their decision in the same manner as in the case of any ordinary offence of a serious nature under the law of that State.
Article 8
1. The offence shall be deemed to be included as an extraditable offence in any extradition treaty existing between Contracting States. Contracting States undertake to include the offence as an extraditable offence in every extradition treaty to be concluded between them.
2. If a Contracting State which makes extradition conditional on the existence of a treaty receives a request for extradition from another Contracting State with which it has no extradition treaty, it may at its option consider this Convention as the legal basis for extradition in respect of the offence. Extradition shall be subject to the other conditions provided by the law of the requested State.
3. Contracting States which do not make extradition conditional on the existence of a treaty shall recognize the offence as an extraditable offence between themselves subject to the conditions provided by the law of the requested State.
4. The offence shall be treated, for the purpose of extradition between Contracting States, as if it had been committed not only in the place in which it occurred but also in the territories of the States required to establish their jurisdiction in accordance with Article 4, paragraph 1.
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