At least 24 people's bodies were discovered at a retired police officer's home in El Salvador.
Officials claim the graves could contain up to 40 bodies, the majority of which are believed to be women or children. It could take another month to exhume all of the remains.
The finding, according to police, exposes a decade-long underground murder ring.
El Salvador has one of the highest rates of femicide, or the killing of a woman because of her gender, in Latin America.
Hugo Ernesto Osorio Chávez, 51, was arrested this month in Chalchuapa for the murder of a 57-year-old woman and her 26-year-old daughter. The retired officer admitted to murdering the couple after previously being arrested for sex crimes.
However, when forensic teams searched his home, which is located 48 miles (78 kilometers) north of San Salvador, they discovered at least seven pits containing bodies, some of which may have been buried as long as two years ago.
The finding, according to police, suggested the existence of a ten-year-long murder ring.
A total of ten people have been charged.
Former police officers, troops, and people traffickers are among the perpetrators, according to Mauricio Arriaza Chicas, chief of El Salvador's national civil police, according to the newspaper La Prensa.
He said that Mr. Osorio Chavez had been murdering people for a decade.