Part II
Extradition
CHAPTER I
Extradition from Portugal
Section I
Requirements
Article 38
Provisional arrest
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.
Provisional arrest - release - ICC proceedings
EDIT.