Wracked by endemic political violence and crime, Karachi is the world's most dangerous megacity. Of the world’s 13 largest cities, Karachi is the most dangerous, according to data compiled by Al Jazeera. This is a living document – it is currently updated with figures from January 1, 2011, to August 31, 2012, and will be continually updated to reflect the city’s ongoing bouts of political and other violence.