EL PASO, Texas (Border Report) – Relatives of missing persons reported finding a mass grave in the Mexican desert 40 miles south of Nogales, Arizona, with the charred skeletal remains of up to 50 people.

The Sonora Attorney General’s Office confirmed a clandestine gravesite was discovered in Santa Ana, Sonora, by the group Colectivo Madres Buscadoras (Mothers’ Search Collective) but disputed the body count from this past weekend.

“In response to the (group), forensic experts from the Attorney General’s Office are making progress in processing the grounds near San Vicente farms past Los Abuelos Lake on the Santa Ana Highway,” the AG’s Office said in a statement Monday. “They confirmed finding two complete skeletons and skeletal remains that could belong to three to four people …”

The mothers’ group on Saturday called the area “an extermination camp,” but later conceded on social media that it doesn’t know how many individuals the skeletal remains belong to. The group says an anonymous caller tipped off its members to the location of the mass grave. It posted graphic videos of the dig on social media.

Sonora state police officers and members of a Mexican nonprofit looking for missing persons examine a mass grave near Santa Ana, Sonora. (photo Sonora Attorney General’s Office)

State government officials said it was premature and “erroneous” to talk about 50 bodies found.

“(We) will continue forensic work in the area to find and recover (evidence) and bring them to the state lab for genetic testing,” the statement said.

Northeast Sonora, where the Sinaloa cartel once controlled most drug trafficking routes to Arizona, in recent years has become a battleground for rival drug cartels, Mexican media report. The Sinaloa cartel is fighting incursions from La Linea (the old Juarez cartel) from Chihuahua, the Jalisco New Generation Cartel from the south and has issues with one of its own cells headed by Rafael Caro Quintero, Nexos reported.

The Sonora state legislature in late 2020 declared a public safety state of emergency due to the proliferation of missing persons resulting from a spike in organized criminal activity. At the time, more than 2,300 people were missing.