One of the basic norms of international law is that law enforcement officers may exercise their functions in the territory of another State only when the consent of the other State is given by duly authorized officials of that State. Certain circumstances, however, make some extraterritorial apprehensions justified under international law, even without the foreign State's consent. The most noted circumstance is based on the right of self-defense which is affirmed in Article 51 of the United Nations (UN) Charter. This article states that nothing should impair the inherent right of individual or collective self-defense if an armed attack occurs against a UN member. Seizure for law enforcement purposes is controversial, but may be tolerated under international law in limited circumstances involving such serious crimes as piracy, genocide, hostage taking, and attacks on diplomatically protected persons. States have an obligation to exercise due diligence in protecting aliens in their territory. Due diligence is based on certain assumptions about the State's ability to fulfill its duty; for example, due diligence assumes that the State can provide protection. Another issue is the concept of hot pursuit which is currently in disfavor under U.S. law. U.S. courts have generally held that when persons accused of a crime are found within the territorial jurisdiction that charged them, the court's jurisdiction is not impaired by the fact that an individual was forcibly abducted to bring him or her into the charging jurisdiction.