JUAREZ, MEXICO - MARCH 26: Police gather at an early morning murder, one of numerous murders over a 24 hour period, on March 26, 2010 in Juarez, Mexico. Secretary of State Hillary Rodham Clinton, Defense Secretary Robert Gates, and Homeland Security Secretary Janet Napolitano all visited Mexico on March 23 for discussions centered on Mexico's endemic drug-related violence. The border city of Juarez, Mexico has been racked by violent drug related crime recently and has quickly become one of the most dangerous cities in the world to live. As drug cartels have been fighting over ever lucrative drug corridors along the United States border, the murder rate in Juarez has risen to 173 slayings for every 100,000 residents. President Felipe Calderon's strategy of sending 7000 troops to Juarez has not mitigated the situation. With a population of 1.3 million, 2,600 people died in drug-related violence last year and 500 so far this year, including two Americans recently who worked for the U.S. Consulate and were killed as they returned from a children's party. (Photo by Spencer Platt/Getty Images) (2010 Getty Images)
MEXICO CITY – Four severed heads have been found packed in Styrofoam coolers left on a roadside in north-central Mexico.
Prosecutors said the gruesome discovery happened on Monday. An official of the Zacatecas state prosecutor's office said the heads were found along with hand-written signs.
The victims have not yet been identified and their bodies have not yet been found.
But the official said the content of the messages suggested the victims were members of a drug gang.
"These are the kind of messages that drug cartels leave for other gangs ... as part of their disputes," the official said.
Photos showed some of the coolers bore the letters "CDG", a reference to the Gulf Cartel, and the words "Welcome to Hell."
The area was once dominated by the highly violent Zetas cartel, much of whose leadership has been arrested or killed.
The Gulf and Jalisco New Generation cartels are now believed to be moving into the area.
Based on reporting by the Associated Press.
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