Drug kingpin Hector Beltran Leyva took responsibility for the killings in a message that was left with the bodies, according to a statement released by the attorney general’s office of Mexico.
The beheaded and mutilated bodies, hung from the bridge by their ankles, were found early on Sunday in Cuernavaca.
A popular weekend getaway for wealthy Mexico City residents, it is also a city besieged by fighting between two druglords since Arturo Beltran Leyva, leader of the Beltran Leyva cartel, was killed there in a December shoot-out with security forces.
Mexican authorities say the cartel split between a faction led by the aforementioned Hector Beltran Leyva, brother of Arturo, and another led by Edgar Valdes Villarreal, a US-born kingpin known as ‘Barbie’ because of his blonde hair.
‘This is what will happen to all those who support the traitor Edgar Valdez Villareal,’ read the message left with the bodies.
After the four men went missing days before their bodies were found, the family of one reported their abduction to police.
Mexico has witnessed unprecedented gang violence since President Felipe Calderon stepped up the fight against drug trafficking after taking office in December 2006, deploying thousands of troops and federal police to cartel strongholds.
Over 28,000 people have been killed in the country’s drug war since.