PORT-AU-PRINCE — The UN Human Rights Office is once again calling for a multinational force to intervene in Haiti after its latest report found that gangs in Haiti have killed at least 531 people, injured 300 and kidnapped 277 since the year began. The UN figures come from a count of reported incidents between January and on Mar. 15. Also as of mid-March, at least 160,000 people have been reported as displaced, the agency said Tuesday.