Mexican soldiers searching mass graves in the state capital of the northern state of Durango recovered 25 more bodies Thursday, bringing the total recovered there to at least 146.
The remains included 23 men and two women, authorities said.
The state prosecutor's office said earlier that autopsies on nine of the bodies recovered in previous days found four had been strangled and one suffocated. The cause of death in the other cases had not yet been determined.
Authorities have not provided a running total of the bodies found over the last month at several sites in the city, also known as Durango, and calls to the state prosecutor's office went unanswered. The newspaper Reforma said the total now stands at 156.
In either case, the number of bodies recovered in Durango appears on track to rival the 183 bodies pulled from clandestine graves in an area of Mexico's northeastern Tamaulipas state just south of the border with Texas.
The two sites, Durango and Tamaulipas, appear to be separate burial grounds for victims of different drug cartels.
The Tamaulipas victims are thought to include many of the passengers reported pulled off passing buses by the Zetas drug gang. Officials say some members of that cartel or their rivals may also have been buried in the graves discovered in April in the township of San Fernando.
The pits in Durango may contain allies of the Sinaloa cartel _ one victim had a tattoo reading "Sinaloa" on his back and an image of Jesus Malverde, considered the patron "saint" of drug traffickers _ but the cartel affiliation of the victims or their killers has yet to be confirmed.
Durango is the scene of a bloody turf war involving the remnants of the Beltran Leyva cartel, the Sinaloa cartel and the Zetas.
Mass graves have become an increasingly common discovery in Mexico, with drug cartels using the sites to dispose of enemies and other victims amid increased fighting among rival gangs. More than 34,600 people have died in drug-related violence since President Felipe Calderon deployed thousands of federal security forces four years ago to fight traffickers.