Part II
Extradition
CHAPTER I
Extradition from Portugal
Section I
Requirements
Article 38
Provisional arrest
1. In case of urgency the provisional arrest of the person sought may be requested as a preliminary to a formal extradition request.
2. Any decision on such a provisional arrest, or on the continuation of such an arrest, shall be taken in accordance with the Portuguese law.
3. Requests for provisional arrest shall: indicate the existence of either a detention order or a sentence against the person claimed; describe briefly the facts that amount to an offence; state when and where such offence was committed, the legal provisions that are applicable, as well as the available data concerning the identity, the nationality and the whereabouts of that person.
4. The provisions of Article 29 shall apply to the transmission of the request.
5. Provisional arrest shall be terminated if the request for extradition is not received within 18 days of the arrest; it may however be prolonged for up to 40 days of the arrest if the reasons given by the requesting State so justify.
6. Provisional arrest may be replaced by any other coercive measure in accordance with the provisions of the Code of Criminal Procedure.
7. The provisions of paragraph 5 above shall not prejudice re-arrest and extradition if a request is received subsequently.
8. The request for provisional arrest shall be examined only where no doubts
arise as to the powers of the requesting authority and if the request contains such elements as are indicated in paragraph 3 above.
Article 39
Non requested provisional arrest
The criminal police authorities may arrest any person who, according to official sources, in particular INTERPOL, is wanted by competent foreign authorities for purposes of criminal proceedings or the purpose of serving a sentence, for any notoriously extraditable offence.
Provisional arrest
Provisional arrest for ICC proceedings - national procedures
EDIT.