MEXICO CITY (AP) — Mexican authorities say they have identified six of the 17 men found dismembered at a farm. Jalisco state prosecutors say two were former military men, two had been imprisoned on undisclosed charges and the other two had criminal backgrounds but had never been jailed.

A Monday statement from the state Attorney General's Office says all 17 victims had gunshot wounds to their heads. They were found naked and stacked with chains around their necks Sunday in the town of Tizapan El Alto, near the border between Jalisco and Michoacan states.

Officials haven't said who they think is behind the killings, but Michoacan is home to the rival La Familia and Knights Templar gangs and Jalisco has seen violence by the Zetas cartel.