MEXICO CITY (AP): Police in southern Mexico found two piles of decapitated bodies containing the remains of 11 men on Thursday.

Photos of the crime scene showed headless corpses stacked on top of one another in a field outside the city of Merida. Some of the bodies had tattoos and were jumbled amid blankets and tarps.

The heads were not immediately found.

It appeared to be the largest single group of beheadings in recent years in Mexico. The tactic has become more frequent in gangland-style killings, and the largest previous instance of decapitations occurred in 2006, when gunmen tossed five human heads into a bar in central Mexico.

The federal attorney general's office confirmed there were 11 dead and it was taking over the investigation _ a move that usually indicates a case involves high-caliber weapons or drug trafficking, both federal offenses.

Merida, located on the Yucatan Peninsula, has largely been spared the drug-gang violence afflicting many other Mexican cities.

Drug hitmen often use decapitations against rival traffickers. The statement by the attorney general's office said, ``The government absolutely rejects any act of violence related to criminal events, even when it is carried out between members of criminal organizations.''