Search teams are excavating a site in the central Mexico state of Guanajuato where 59 bodies have been found in clandestine graves in the past week.

The striking aspect of the discovery is that the site is not a desolate area far out in the countryside, but the town of Salvatierra.

The head of the official National Search Commission, Karla Quintana, said in an interview with W Radio on Thursday that people had to have known that bodies were being disposed of there. “This place is in a neighbourhood,” Quintana said. “To get there you have to pass homes, you have to pass streets … the people know.”

Quintana said the tip came about two weeks ago from relatives looking for missing loved ones. She said searchers had found indications of more bodies there, so the search is continuing. The goal is to recover the bodies, identify them and return the remains to their families, she said.

Announcing the find late on Wednesday – “a sad and terrible discovery” – Quintana said many of the victims seemed young, and there were a significant number of women among them.

The bodies were extracted from 52 pits at a property in Salvatierra. The scene was considered dangerous enough that the army and National Guard provided security for the excavations. The area is near the border with Michoacan state and there is known to be a significant organised crime presence in the region.

Guanajuato has the largest number of homicides of any state in Mexico, and has been the scene of bloody turf battles between the Jalisco cartel and local gangs backed by the Sinaloa cartel.

The find represents the largest such burial site found to date in Guanajuato, though bigger clandestine burial sites have been excavated in other parts of Mexico.

President Andrés Manuel López Obrador said on Thursday that the situation in Guanajuato was “very difficult”. He said the deployment of the National Guard in the state was at least allowing authorities to reach areas that were previously inaccessible due to the organised crime presence.