CAT/C/PRT/CO/4 page 6 concerned by reports of numerous acts of violence of a discriminatory nature directed against certain minorities. The Committee is also concerned that the membership of the police forces does not reflect the diversity of minorities present in Portugal (art. 16). The State party should take the necessary measures to effectively combat acts of violence based on any form of discrimination and to punish the perpetrators appropriately. The State party should also strive to include representatives of minorities residing in its territory in the police forces. 18. The State party is encouraged to consider ratifying the Optional Protocol to the Convention. 19. The Committee invites the State party to ratify the major United Nations treaties on human rights to which it is not yet party. 20. The State party is encouraged to disseminate widely the reports submitted by Portugal to the Committee and the Committee’s conclusions and recommendations, in the national language, through official websites, the media and non-governmental organizations. The State party is also encouraged to circulate its reports to national non-governmental human rights organizations before submitting them to the Committee. 21. The Committee invites the State party to submit its core document in accordance with the requirements concerning the common core document contained in the harmonized guidelines on reporting, adopted by the international human rights treaty bodies and contained in document HRI/GEN/2/Rev.4. 22. The Committee requests the State party to provide, within one year, information on its response to the Committee’s recommendations as contained in paragraphs 11 to 14 above. 23. The Committee, having concluded that, during the consideration of the report of the State party, a sufficient amount of information was adduced to cover the period of the delay in submitting its fourth periodic report, decided to request that the sixth periodic report should be submitted by 30 December 2011. -----