Hugo Ernesto Osorio Chávez’s neighbours never noticed anything suspicious at the former police officer’s house in El Salvador, they told La Prensa Gráfica.

Until one evening in May, when a woman’s cries brought police to the house, where they discovered the bodies of two women inside the residence and two men in a nearby septic tank.

In the following days, authorities made an even more gruesome find at the home in Chalchuapa, about 77km northwest of San Salvador: a pit in the backyard with buried human remains dating back to 2019.

So far, authorities have found at least 12 bodies inside the pit, most of them belonging to women and girls as young as two years old, the nation’s general district attorney announced last week – and many more could be inside the grave.

Along with Mr Osorio Chávez (51), whom authorities described as a “psychopath”, police have charged nine others in connection with the bodies found and say the suspects may have been part of a murder ring targeting women.

“We don’t know at this time how many more bodies we have in this house,” Max Muñoz, a district attorney, said during a Friday news conference. “So far, we are still only working in the pit.”

The case has illuminated once again Latin America’s crisis of femicides, the murders of women and girls due to their gender – a deadly trend that has gripped El Salvador, which recorded 70 women killed in such attacks last year.

The Central American nation, which grappled with thousands of disappearances during its brutal civil war, faces a similar issue three decades later, The Washington Post recently reported – only now, the threats come from gangs and drug cartels. Until mid-April, El Salvador’s national police had reported 577 missing people reports, 17pc more than the number of complaints filed last year during the same period.

Mr Osorio Chávez was dismissed from his post with the National Civil Police 15 years ago for having sexual relations with a minor and raping an underage person. He spent five years behind bars for that case. Even before his arrest, authorities suspected Mr Osorio Chávez was a member of a gang.

His neighbours, though, described him as a “nice person” who “would not mess with anyone”, La Prensa Gráfica reported.

Around 11pm on May 7, Jackeline Cristina Palomo Lima (26) rushed out of Mr Osorio Chávez’s home pleading for help moments before the former policeman allegedly killed her and her mother, Mirna Cruz Lima (57), Ms Lima’s grandfather told El Diario de Hoy. Ms Lima had given Mr Osorio Chávez $7,000 (€5,700) to bring her brother, Alexis Palomo Lima (23), to the United States, Ms Lima’s grandfather said.

His body was one of the two found inside a septic tank. So far, Mr Osorio Chávez has not been charged in connection with the deaths of those two men, according to local media reports. Mr Osorio Chávez was arrested that evening and transported to a maximum-security detention centre, authorities said. “Given the level of danger Osorio Chávez presents, he will be locked up in a cell where he won’t even receive sunlight,” police tweeted.

Hours later, forensic investigators sporting white hazmat suits and masks arrived at the home with shovels, picks and buckets tied with ropes to begin excavating near the property. The team has continued digging for days. Authorities expect the recovery process to last several weeks.

“Bodies are being taken out and more bodies can be seen in the ditch,” Mr Muñoz said at the Friday news conference. Nayib Bukele, El Salvador’s president, referred to Mr Osorio Chávez as a “serial murderer”.