A woman attends a memorial by non-governmental organization (NGO) Rio de Paz (Rio of Peace), held in memory of police officers from the Police Peacekeeping Unit (UPP) who were killed while carrying out their duty, in downtown Rio de Janeiro March 17, 2014. The introduction of the peacekeeping program in the Rio de Janeiro slums is part of efforts to crack down on crime and increase security as the city prepares to host the 2014 World Cup soccer tournament and the 2016 Olympic Games. [Photo/Agencies]