 During peak years of violent crime in the city, gun battles between rival cartels, and between cartels and the police, erupted in public.In April 2008, police found 1,500 shell casings on various streets after one battle left 13 suspected drug traffickers dead.In 2009 and depending on the source, Tijuana Municipality experienced either 556 or 1,118 murders, mostly as a result of the drug war.