DURANGO, Mexico — The backhoe finally fell silent, and investigator Jesus Salvador Romero stepped out of the compound of Mexico's latest mass grave site, tugged off a surgical mask and issued a matter-of-fact report on the ghastly scene: The site had yielded 11 bodies in a few hours.
"None of them had bullet wounds. None were stabbed. They all seem to have been strangled using a rope tourniquet and a stick," Romero said.
In less than a month, the upturned killing fields of this colonial city had given up 180 bodies by Tuesday, by official count, a horrific tally that's forced the local morgue to rent a Thermo King refrigerator truck.
And the ground keeps offering fresh bodies, making it seem likely that Durango's mass graves soon will eclipse what previously had been the largest set of unidentified corpses uncovered in Mexico: last month, in northeast Tamaulipas state, where 183 bodies piled up.
Never have such massive killing fields been found in such a short time in Mexico or anywhere in the Western Hemisphere, for that matter. The victims were lost to violence that only seems to intensify in a nation where prosecutors treat evidence shoddily and rarely bring mass murderers to justice. Most of the victims are likely to remain unidentified.
"It's appalling," said Joy Olson, the executive director of the Washington Office on Latin America, a social justice advocacy group. Mexicans are vanishing at an increasing pace, she added. "They are disappearing, and where's the outrage?"
Last month, a journalistic tally by the newspaper Reforma determined that 156 mass graves have been uncovered since President Felipe Calderon came to office in late 2006. Mass graves that once held a dozen or two corpses now yield much higher body counts, all of them probably imprecise.
In Durango, for example, the Mexico City newspaper El Universal claims the total already surpasses 190, but El Universal is counting 13 bodies found in Santiago Papasquiaro in an outlying part of Durango. Compounding the confusion, it's uncertain how to count random body parts, including heads, that are dug up.
Such mass killings have only a few parallels in this hemisphere. One would be Argentina's "dirty war," when thousands of leftists died or disappeared during the 1976-83 military rule. Another might be the El Mozote massacre in 1981 in El Salvador, when U.S.-trained troops killed hundreds of villagers.
International experts urge Mexico to exhume the mass graves with an eye to building legal cases and to act more vigorously to identify and search for citizens declared missing.
"The fact that we're seeing all kinds of people turn up in mass graves underscores the need for Mexico to create a national database for people who have disappeared," said Nik Steinberg, the Mexico researcher for Human Rights Watch, a New York-based advocacy group. No such database now exists.
An anonymous caller first tipped Durango law enforcement officials to a mass grave site in mid-April. Other calls pointed to two other clandestine cemeteries. Since then, only one corpse has been identified, a 31-year-old man from a part of the state dominated by the Sinaloa Cartel, considered Mexico's most powerful narcotics and crime syndicate.
Officials suspect that some of the victims are foot soldiers from rival Sinaloa factions — Los M and Los Cabrera — that began fighting earlier this year. Others are thought to be kidnapping victims and other innocents.
"It will be a titanic task for prosecutors to identify these people," said Carlos Garcia Carranza, the head of the Durango State Human Rights Commission, a largely toothless but official government body.
Some of the victims may be migrants from distant states, their families too poor to make the journey to provide identification. Moreover, the way the bodies were uncovered mangled many of them.
"They are doing it with heavy machinery. The authorities have lacked sensitivity in how to remove the bodies one by one," Garcia Carranza said.
Experts on mass graves, such as those in Argentina or the former Yugoslav republics, where ethnic cleansing was rampant, say the work must be done with the precision of an archaeological excavation.
"Exhumation by backhoe is tantamount to tampering; evidence is likely to be irretrievably lost," said Gordon Housworth, who follows Mexico closely for Intellectual Capital Group, a consultancy in Franklin, Mich.
Housworth said clumsy handling of the graves wasn't the sole problem.
"Add to that the tiny number of coroners, especially forensic coroners, lack of sustained site protection . . . limited DNA and genetic testing, high case backlogs and historic reticence of relatives to come forward, and the chances of proper due diligence are diminished," he said.
A spokesman for the state prosecutors' office, Gerardo Ortiz, said the graves were too big for shovel work, making heavy machinery a necessity. He added that the criminal investigation is going slowly. Neighbors have been of little help.
"Anybody who might have seen something will never talk out of fear," Ortiz said, brushing off questions about who owns the land where the graves were found. Pressed further, he said, "Do you want me to wake up alive tomorrow?"
The Durango governor's chief security aide, Juan Rafael Rosales, was equally uneasy talking about the subterranean criminal conflicts that have roiled the state, resistant even to utter the names of gangs or talk about the banners the groups occasionally hang from bridges or buildings, which disappear only hours later.
The head of the National Action Party in Durango, Juan Carlos Gutierrez, an opponent of the governor, said criminal groups composed a "parallel state" in Durango.
"They collect extortion — a kind of tax — and they have armed forces that seem almost like a clandestine army," Gutierrez said. "These are the characteristics of a state: have an army, collect taxes, maintain peace."
But the mass graves reveal that there is no peace, and that powerful criminal groups are doing the killing.
"Mass graves infer organization, sustained presence and the expectation that the site can be protected from discovery for a substantial period," Housworth said.
The mass graves of Durango and Tamaulipas state, which abuts Texas, are quite different. Most of the bodies in the Tamaulipas graves appear to be of passengers on two interstate public buses pulled off by hooded members of Los Zetas, a brutal drug gang, who gave them a choice: Join the gang or face execution.
Alejandro Poire, a federal spokesman on security issues, said those found in the graves probably "resisted and because of that these criminals cunningly finished them off."
San Fernando, a Tamaulipas city 100 miles south of Brownsville, Texas, has a grisly recent history. Eight months ago, presumed Zetas executed 72 unarmed Central American migrants on a ranch there, leaving them crumpled in puddles of blood. A wounded Ecuadorean escaped and alerted authorities.
Given that event, each new report of a mass grave sends shivers south of Mexico into Central America. Last week, Guatemala's Foreign Ministry sent Mexico detailed information about 34 migrants who it said had vanished in the country.
In Durango, however, weariness with disinterring mass graves has set in. At one of the graves, an open compound that appeared to have served as an auto workshop, Romero, the investigator, said he had no idea who the victims were.
"We just see dead people," Romero said. "We don't know if they are criminals, if they were kidnap victims or if they died by being in the wrong place at the wrong time."
But the work doesn't seem to stop.
"The word going around is that they are looking for a single mass grave with more than 100 bodies," said Gutierrez, the state politician.
Local journalists said a state police commander told them that an anonymous call came in about the alleged grave site along the highway to Mazatlan. But he added that the state didn't have resources to keep looking for such graves.
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