Four decapitated bodies have been found hanging from a bridge in Mexico's Sinaloa state, part of a surge of violence that claimed the lives of 20 people in less than a day

Mexican authorities in Sinaloa state said 20 people were killed, including some who were decapitated, in the latest episode of cartel-driven violence.

A van containing 16 of the bodies was plastered with a banner referencing the ongoing wars between rival drug cartels in Sinaloa, authorities said.