Bangui - The UN Secretary General Antonio Guterres paid tribute on Wednesday to the thousands of the UN peacekeepers in Central African Republic, the site of one of the UN's most dangerous missions and the most sexual misconduct allegations against peacekeepers and UN personnel last year.The UN chief attended a wreath-laying ceremony in the capital of Bangui. A dozen peacekeepers have lost their lives so far this year amid escalating violence in the long-volatile country."We need to make sure that the world fully appreciates the heroic contributions of peacekeepers protecting civilians, sometimes in extremely difficult circumstances, like the ones we face in the Central African Republic," Guterres said."I am very proud to be your colleague. I am very proud to serve in the same United Nations where you serve," he said. "And I want to tell all of you Blue Helmets here with us that we count on you to make the UN always more effective serving the people."Sexual misconduct Violence erupted in late 2013 and untold thousands died during 2014 before the UN took over for a regional peacekeeping operation. In recent months, civilians have urged the UN to increase the size of the force. Amid a rise in attacks, many communities say they remain vulnerable in largely anarchic outlying regions.Guterres has recommended that the number of peacekeepers be increased by 900 to a total of about 12 000, though it is unclear which countries would provide the troops. Contingents from Congo and the Republic of Congo have been repatriated amid allegations of sexual misconduct.The UN chief has said that sexual abuse and exploitation is a problem throughout the UN. He vowed at the General Assembly last month to root out the problem "once and for all." On his trip to Central African Republic, he was accompanied by the UN's first victims' rights advocate, Jane Connors.Critics have pointed to a variety of factors that have led to such a high number of sexual misconduct cases in Central African Republic, including poor vetting of the troops who were incorporated into the UN mission. Extreme poverty and food shortages also have made girls and women in the country particularly vulnerable to sexual exploitation, observers say.