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18 dismembered bodies found near Guadalajara, Mexico

Alejandro Acosta / Reuters

Forensic technicians handle bags containing human remains found in two abandoned vehicles near Guadalajara, Mexico, on Thursday.

MEXICO CITY -- Police found the decapitated and dismembered bodies of 18 people near Mexico's second-largest city, Guadalajara, on Wednesday, in what appeared to be the latest atrocity by the country's most brutal drug cartel. 

Thought to have been carried out by the Zetas gang, it was one of the biggest mass beheadings in the recent history of Mexico, where decapitations have become alarmingly common.

The bodies and heads were stuffed into two vehicles abandoned on the side of a highway in the small town of Ixtlahuacan de los Membrillos, said Tomas Coronado, chief prosecutor for the state of Jalisco. 

Ixtlahuacan de los Membrillos is located 18 miles south of the center of Guadalajara on the road to Lake Chapala, a site popular with foreign tourists and U.S. retirees.

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Some of the bodies had been refrigerated before they were dumped, Coronado said.

A policeman at the scene in Ixtlahuacan said some victims had been so badly mutilated that officers could not determine whether they were male or female.

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The officer said a note by the bodies was signed by the Zetas cartel, a criminal militia led by former Mexican soldiers and blamed for some of the worst atrocities in Mexico's drug war.

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"They are clearly messages between rival groups that are in conflict," Coronado told The Associated Press.

The AP reported that the vehicles, described as minivans, were towed to government offices to unload the bodies.

Guadalajara, known for its high-tech industry, mariachi bands and tequila, has been a strategic base for drug traffickers since the 1980s. 

Violence has flared in the once-tranquil city as the Zetas moved in to challenge the smuggling turf of other gangs in western Mexico.

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Soldiers arrested a high-ranking member of the powerful Sinaloa cartel in the city in March, causing his supporters to block streets with 25 burning cars and trucks.

Mexico's drug war is also part of a drug culture with roots in music, movies and even religion.

Attacks between the Zetas and their rivals have flared up across Mexico since the beginning of the year. 

On Friday, nine corpses were hanged from a bridge in the border city of Nuevo Laredo just hours before 14 bodies were dismembered and shoved into garbage bags and ice boxes. 

Five days of intense battles in western Sinaloa state last week also left 34 dead, adding to the body count in Mexico's drug war, which has killed more than 50,000 people in the past five years.

Msnbc.com staff and Reuters contributed to this report.

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