Jacksonville
If you mean US city, it is Chicago with about 500 murders.
New orleans
For the United States, New Orleans, LA, has had the highest number of homicides for the last ten years. Internationally, Ciudad Jaurez, Mexico, comes in first with over 2,600 murders.
gary
Ciudad Juarez, Mexico. In 2009 there were 2,658 killings.
The city with the most murders in 2007 was Detroit, Michigan.
Ciudad Juarez, Mexico with 191 murders per 100,000 last year.
Right now (Dec 2013) it would be Acapulco, on the southern state of Guerrero. It is the second most dangerous city in the world, with 143 murders per 100,000 inhabitants.
New York,NY with 523 followed by Chicago at 510
the state and city of the murder of samtha finley
over 100000 if you count the genocides going on as murders