It is axiomatic that a reasonable search is not to be determined by any fixed formula but is to be resolved according to the facts of each case. Given the circumstances obtaining here, we find the search conducted by the airport authorities reasonable and, therefore, not violative of his constitutional rights. Hence, when the search of the box of piaya revealed several marijuana fruiting tops, appellant is deemed to have been caught in flagrante delicto , justifying his arrest even without a warrant under Section 5(a), Rule 113 of the Rules of Criminal Procedure. The packs of marijuana obtained in the course of such valid search are thus admissible as evidence against appellant. 130 (Citations omitted) The reason behind it is that there is a reasonable reduced expectation of privacy when coming into airports or ports of travel: Persons may lose the protection of the search and seizure clause by exposure of their persons or property to the public in a manner reflecting ...