Mexico's human rights ombudsman Wednesday blamed the army for the April shooting deaths of two children that stoked a raging debate over the military's role as a domestic police force.
Raul Plascencia, president of the National Human Rights Commission, rejected the military's assertion that the van in which the two boys were riding near the U.S. border was caught in a cross-fire between soldiers and gunmen.
Plascencia said the wounds resulted from "direct and discretionary" fire by Mexican troops.
Five others in the van were wounded in the Easter weekend incident, which took place on a highway in Tamaulipas state where drug-trafficking organizations have engaged in fierce clashes.
Family members of the boys, ages 9 and 5, have said masked men in uniforms started shooting after the van's occupants rolled down the windows and slowly drove past what appeared to be a military checkpoint.
Members of the Almanza family, which was on its way April 4 to a beach outing on the Gulf of Mexico, said they were attacked with guns and grenades even after crying for mercy and trying to flee on foot.
The army exonerated itself April 30, saying the family had been attacked by drug gang gunmen, not troops, at the checkpoint and then became caught in a shootout between soldiers and the hit men.
But Plascencia said in his nonbinding report that the military's finding "has no substance or adherence to the evidence," and suggested that the army had altered the scene to support a cross-fire explanation by firing bullets into the vehicle afterward.
The military issued no immediate comment on the report.
The incident ignited an outcry over the deployment of about 50,000 troops around Mexico as part of President Felipe Calderon's 3 1/2-year-old crackdown against drug traffickers.
While many residents of drug-plagued areas welcome soldiers, the deployment has spurred widespread allegations of abuse by troops, including torture and unlawful detention.
Rights activists say they are concerned that the military is allowed to investigate itself, usually without public accounting, in cases in which troops are accused of wrongdoing.
Concerns over possible abuses prompted the U.S. Congress to add human rights guarantees as part of the $1.4-billion security aid package for Mexico known as the Merida initiative.
Domestic critics of the massive drug-war deployment worry that the army, traditionally one of Mexico's most respected institutions, risks being tainted by corruption.
Also Wednesday, six people were shot dead outside a drug treatment clinic in the border city of Ciudad Juarez, the latest attack on a rehab center, authorities said.
On Thursday, masked gunmen stormed a treatment facility in the northern city of Chihuahua, killing 19 residents. Clinics in Juarez have suffered several attacks, including one in September that killed 18 people. Authorities say the centers have been targeted by gang members because they can serve as hide-outs for rivals.