MEXICO CITY - Twenty-nine people were probably executed by drug gangs in the southern Mexican port city of Acapulco in less than two days, including four corpses found on Sunday, authorities said.

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The corpses, all beheaded, were deserted on a rural road with written messages attached to them, according to a statement by the Public Security Department (SSP) of the Guerrero state where the city is located.

The department also said police found the bodies after receiving an anonymous call and the messages are related to Joaquin Guzman, boss of the Sinaloa drug cartel.

On Saturday, twenty-five corpses where found in different locations in Acapulco, with 15 of them beheaded.

More than 30,000 people have been killed in drug-related violence since the Mexican government launched an iron-fist crackdown on drug gangs four years ago, according to local press.