Forty-nine decapitated and mutilated bodies were found on a highway Sunday near Mexico’s third-largest city of Monterrey.

Mexican prosecutors said the bodies were severely damaged and identifying victims will be difficult.

Investigators believe that the 43 men and six women were killed in a recent bout of violence between drug cartels.

Mexican President Felipe Calderon declared a war with drug gangs after taking office in 2006. Since then, 47-thousand-500 people, mainly gang members, have been killed.