Violence has soared in Sinaloa since the capture in the U.S. of cartel co-founder Ismael "El Mayo" Zambada almost a year ago.

Twenty bodies, several of them decapitated, were found on a highway bridge in a part of Mexico where factions of the Sinaloa drug cartel are fighting each other, authorities said Monday.

Four headless corpses were found by the roadside while 16 bodies were discovered inside an abandoned vehicle, the Sinaloa state prosecutor’s office said.

Five human heads were found inside a bag at the scene. All of the bodies showed signs of gunshot wounds, prosecutors said.