TUCSON, Ariz. – A group of Mexican mothers, known as Searching Mothers of Sonora, uncovered a mass grave that was originally thought to hold at least 27 bodies near the popular beach resort town of Puerto Peñasco. As the search continues, more than 14 additional bodies have been found, according to USAToday.

It is unclear just how long the unidentified bodies have been buried; fortunately, staff members from the attorney general’s office and forensic workers from the state’s criminal investigations unit have joined in the search and will help transport and identify the remains.

The Searching Mothers of Sonora describes themselves not as a group looking for perpetrators, but as “mothers searching for missing persons or human remains, to bring peace to other families that are going through the same pain.”

Although Puerto Peñasco has been a safe-haven in an area known as a profitable drug and human smuggling route, there has been the occasional cartel-related gunfight over the years.

The city is a key source of tourism revenue for the state, but an increasing number of visitors come from Arizona, making it a priority for both states.