On Saturday, the Sonora state prosecutor's office said in a statement it had sent forensics experts into the field to accompany a volunteer search group that helped discover what was estimated to be 27 sets of human remains. Late Sunday, the group called "Guerreras Buscadoras," or "Warrior Searchers," said it found three more sets of remains in a field near the northern city of Cajeme.
The group is comprised of mostly women who organize their own digging teams for missing relatives in the face of official inaction.
"The Warrior Searchers are not alone in their hope of finding their loved ones, the Sonora prosecutors' office is accompanying them," the office said.
On Sunday, the government of the north-central state of Guanajuato also said that state or local police will accompany Red Cross ambulances "on the high risk or high-impact calls." That would presumably be calls related to gunshot victims.
A day prior, a man wounded by gunfire was abducted by gunmen from a Red Cross ambulance in the city of Salamanca, which has been plagued by violence between fuel theft gangs due to its gasoline refinery. The Guanajuato state chapter of the first-aid group shuttered operations in the city of 270,000 but later resumed ambulance service.
In a statement, the Mexican Red Cross said it "is an impartial and neutral institution before all conflicts and its purpose is to relieve human suffering," adding the "#We are not part of the conflict" hashtag.
Violence in Mexico has worsened in the last year, with homicides running at their highest rate on record and surpassing the previous peak set in 2011.
Earlier this month, a woman with gunshot wounds was executed inside an ambulance in Mexico's Pacific state of Guerrero, and paramedics were reportedly beaten by the perpetrators.
Recently, the archdiocese of the central state of Puebla said in a statement that Rev. Ambrosío Arellano Espinoza, a 78-year-old priest, was apparently tortured during a robbery attempt. It said he had been found with severe burns on his hands and feet, but was at a hospital in stable but serious condition.
Clandestine burial sites have often been used by drug cartels in Mexico to hide the bodies of executed rivals or kidnap victims.
While hundreds of such sites date back to the height of the drug war from 2010 to 2016, some are more recent.
Searchers in Mexico generally count the dead by the number of skulls, but not all heads are always present at the time of burial, suggesting death tolls could be even higher.
Volunteer searchers often act on tips about where burial grounds are located and then walk through fields plunging rods into the earth to detect the telltale odor of decomposing bodies.
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