Coordinated Operation Chihuahua or formerly known as Joint Operation Chihuahua is a Military and Federal Police operation started in 2008 by the Mexican Army and Policía Federal Preventiva. The objective is to "besiege" Ciudad Juárez to concentrate forces and saturate the area to confront the three cartels already operating in the city. Ciudad Juárez is known to be one of the most dangerous cities in the Americas.