OAU Convention on the Prevention and Combating of Terrorism, 1999 whatsoever; (b) develop and strengthen methods of monitoring and detecting plans or activities aimed at the illegal cross-border transportation, importation, export, stockpiling and use of arms, ammunition and explosives and other materials and means of committing terrorist acts; (c) develop and strengthen methods of controlling and monitoring land, sea and air borders and customs and immigration checkpoints in order to pre-empt any infiltration by individuals or groups involved in the planning, organization and execution of terrorist acts; (d) strengthen the protection and security of persons, diplomatic and consular missions, premises of regional and international organizations accredited to a State Party, in accordance with the relevant conventions and rules of international law; (e) promote the exchange of information and expertise on terrorist acts and establish data bases for the collection and analysis of information and data on terrorist elements, groups, movements and organizations; (f) take all necessary measures to prevent the establishment of terrorist support networks in any form whatsoever; (g) ascertain, when granting asylum, that the asylum seeker is not involved in any terrorist act; (h) arrest the perpetrators of terrorist acts and try them in accordance with national legislation, or extradite them in accordance with the provisions of this Convention or extradition treaties concluded between the requesting State and the requested State and, in the absence of a treaty, consider facilitating the extradition of persons suspected of having committed terrorist acts; and (i) establish effective co-operation between relevant domestic security officials and services and the citizens of the States 209