CAT/C/PER/CO/5-6 (b) Adopt reasonable time frames for the construction of new prisons and the expansion and renovation of existing places of detention; (c) Ensure that there are sufficient medical professionals, including mental health professionals, in places of detention; (d) Use solitary confinement as a last resort, for as short a time as possible, with the possibility of judicial control; (e) Ensure that the prisoners in the high-security prison in Callao are treated in conformity with the United Nations Standard Minimum Rules for the Treatment of Prisoners; (f) Consider closing the Challapalca and Yanamayo penitentiary centres. Designation of a national preventive mechanism 11. The Committee is very concerned that six years after its accession to the Optional Protocol to the Convention, the State party has still not set up the national preventive mechanism (art. 2). The State party should without further delay establish the national preventive mechanism in full compliance with the Optional Protocol and in particular grant it sufficient financial, human and material resources in order to assume its mandate effectively. Use of force 12. The Committee is concerned at allegations of excessive and disproportionate use of force, including firearms, by the national police and armed forces during social protests as well as arrests of human rights defenders, lawyers, representatives of the Ombudsman and members of the indigenous population during such situations, and that to date there have been no convictions regarding the incidents in Bagua, Celendín or Bambamarca (arts. 2, 10, 12, 13 and 16). The State party should: (a) Ensure that law enforcement officials receive training on the absolute prohibition of torture, and on in international standards on the use of force and firearms, including on the liabilities in cases of excessive use of force; (b) Expedite the investigation and prosecution of such cases and sanction officials found guilty of such offences with appropriate penalties. States of emergency 13. The Committee is concerned at the frequent imposition of states of emergency, during which restrictions on human rights may give rise to violations of the Convention and that state of emergency has been imposed in relation to peaceful social protests. The Committee is further concerned at the promulgation on 1 September 2010 of Legislative Decree No. 1095 allowing military courts to decide on cases of excessive use of force and human rights violations during state of emergency (art. 2). The State party should limit the imposition of state of emergency to situations in which it is strictly necessary, and at all times respect the provisions of the Convention stating that no exceptional circumstances may be invoked as a justification of torture. The State party should consider amending Legislative Decree No. 1095 with a view to bringing all its provisions in line with the State party obligation under the Convention. 4