An autopsy carried out on the body of drug cartel leader Heriberto Lazcano before his body was stolen shows he died of six gunshot wounds, including two to the head, according to a forensic report released Thursday.

The Coahuila state prosecutors' office said the autopsy determined Lazcano died of brain injuries, hemorrhaging, shock and blood loss. Lazcano, known as "El Lazca," was a founder and one of two top leaders of the brutal Zetas drug cartel and was one of Mexico's most-wanted drug lords.

The head wounds stood out, given navy reports indicating Lazcano was shot at a distance of as much as 300 meters (yards) by marines during a confrontation in northern Coahuila state Sunday.

The autopsy report said Lazcano was shot once in the side or top of the skull and once in the back of the head. The four other wounds were in the buttocks, chest and arm.

Masked men stole his body from a funeral home early Monday. State forensic experts performed the autopsy at the funeral home Sunday evening, before the body was stolen.

Mexico's navy said its personnel had no idea they had killed the leader of the country's most-feared drug cartel until after his body was stolen. By law, military personnel in Mexico cannot keep or examine suspects or corpses, but must turn them over to civilian prosecutors. In areas where morgues are in short supply, medical examiners sometimes perform autopsies at funeral homes.

The navy says Lazcano was killed after marines tried to search a group of suspicious men in a truck outside a baseball stadium, after receiving a tip there were armed men in the area. The men fired when the marines stopped the truck. One suspect died where the truck was stopped, but the man later identified as Lazcano fled across a field, where he was reportedly cut down by marine fire.