The Horrifying Story of Pedro Lopez: South America’s Missing Serial Killer

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In this article:

• Pedro Lopez was convicted for killing hundreds of people, mostly young girls, between 1969 and 1980.
• By targeting indigenous girls (who are typically neglected by justice systems), Lopez was able to torture and kill over 450 people before attracting the attention of authorities.
• Despite the magnitude of his crimes, he was released from prison early for good behavior. His whereabouts today are unknown.

Trigger warning: descriptions of sexual abuse, pedophilia, violence, murder.

Most stories about serial killers have an ending. The killer is caught, the bodies are found, and the rest of us are left to speculate about the murderer’s motivations and mental afflictions. This is not the case with Pedro Lopez, one of South America’s most notorious serial killers.

Dubbed the Monster of the Andes, Lopez is believed to have killed hundreds of people between 1969 and 1980, most of them being young girls. While many of those living outside of South America may not have heard of Pedro Lopez, he was named the “most prolific serial killer” by the Guinness Book of World Records in 2006. This record was later removed from the book because of complaints saying it made a competition out of killing. 

Well, if killing were a competition, Pedro Lopez would probably be the winner. Not only because he’s believed to have killed over 450 people, but because he was allowed to walk free after doing so.

In fact, there’s a chance that you could walk by Pedro Lopez on the street today. That’s right; he’s still at large. No one knows this vicious killer’s whereabouts or even if he’s still alive. While he would be 73 years old now, there’s still a chance that Pedro Lopez is still out there in the world claiming the lives of even more victims.

You may find it unbelievable that such a monstrous killer was allowed to walk free after committing hundreds upon hundreds of murders. You’d be right to do so. The story of Pedro Lopez not only calls into question the darkest parts of the human psyche, but also the penal systems of the countries in which Lopez committed his crimes. In fact, these very same penal systems may, in fact, be partially responsible for turning Pedro Lopez into the monster that he has become. 

The Making of the Monster

Pedro Alonso Lopez was born in Colombia in 1948 and raised by his mother Benilda Lopez de Castaneda, who conceived Pedro after having an affair with a married man. Like many other serial killers, Lopez had a traumatic childhood.

Lopez’s father was murdered six months before Pedro was born. The first known instances of trauma in Lopez’s life were witnessing his mother engage in sex work, which he claimed had a disturbing effect on his psyche. While Lopez’s mother claimed to be loving and caring, Pedro Lopez said that she was physically and emotionally abusive

Pedro Lopez’s life took a twisted turn in 1957 when his mother caught him fondling his sister. He was kicked out of his home at the age of 9. While wandering the streets, Pedro Lopez was picked up by a pedophile who lured him into his home with the promise of food and a place to stay. Instead, Pedro was taken to an abandoned building and raped repeatedly. 

After this incident, Pedro joined a street gang of children to protect himself from further predation. The gang would commit petty crimes and smoke a derivative of cocaine. After four years of living on the street, Pedro Lopez was taken in by a family from the United States and put in a school for orphans.

Not long after, though, he ran away. By some accounts, it was because he was molested by a male teacher. Other accounts claim that he ran away with the teacher. 

Back on the streets and 18 years old, Pedro Lopez started making a living by stealing cars and selling them to local chop shops. Eventually, he was caught by the police and sent to prison. While in prison, Lopez was brutally raped by three other inmates.

In an act of retaliation, Lopez fashioned himself a weapon and killed all three of the rapists, one of them with his bare hands. These killings earned him the respect of his fellow inmates, none of which ever tried to harm him again.

The killings were also considered to be in self-defense by the Colombian justice system, so only two years were added to Lopez’s sentence. This incident would mark the beginning of the long string of killings and legal free-passes that were to come. 

Terror in the Andes

Once Pedro Lopez was released from prison, he moved to Peru and his reign of terror ensued. He began kidnapping, raping, and murdering girls with horrendous frequency. At the height of his crime spree, he was apparently murdering around three girls per week.

Most of his victims were girls between the ages of 9 and 12. When asked about his motivation for killing young girls, he said, “I lost my innocence at age of eight. So I decided to do the same to as many girls as I could.”

Lopez would stalk his victims from afar, sometimes for several days before making his move. Then, he would kidnap the girl, lead them out to a secluded place, rape them, and strangle them to death. He would bury their bodies in shallow graves.

Sometimes, before the bodies had decomposed too much, he would return to the graves, dig them up, and have “tea parties” with groups of corpses. Lopez claimed that he preferred to kill during the day so that he could see his victims’ faces when they died. 

Most of Lopez’s victims were girls from poor indigenous communities. According to Lopez, he didn’t have a preference of which ethnicity his victims were, it was simply a matter of practicality that most of his victims were from indigenous communities where children were looked after less closely.

On one occasion, Lopez was caught in the act of trying to kidnap a girl from one of these communities. The locals beat him, tortured him, and eventually buried him up to his neck. They planned to cover his head in syrup and let ants eat him alive. But, he was saved when an ambassador from the United States convinced them to let him go free. 

On another occasion, in Ecuador this time, Lopez was again caught in the act of trying to kidnap a girl by the girl’s mother. When the mother began to shout for help, an angry mob formed that would have lynched Lopez right there on the spot if he hadn’t been rescued by police officers.

The officers eventually took Lopez into custody and interrogated him. It was at this point that the true extent of Lopez’s crimes was revealed. 

At first, the interrogators believed that Lopez was part of a gang that had been abducting girls around Ambato, Ecuador. No one could have imagined that so many missing children could be traced back to a single man. However, Lopez eventually confessed that he had killed one of the missing girls police were looking for. When the officers asked him if he had murdered any more girls, he replied, “Over two hundred in Ecuador, some tens in Peru, and many more in Colombia.”

Behind Bars 

Lopez led the authorities to 53 shallow graves that he’d dug around Ambato and several more that he’d used to bury victims in other parts of the country. It’s believed that he killed at least 110 people and some estimates are a whole lot higher.

Pedro Lopez was sentenced to 16 years in prison, the maximum penalty for murder in Ecuador. He was released two years early, in 1994, for being a model prisoner and exhibiting good behavior. 

Within an hour of being released, he was arrested for illegally crossing the border into Ecuador and deported back to his home country of Colombia. In 1995, Pedro Lopez was put on trial in Colombia for murder, but he was declared insane and sent to a mental hospital instead of prison.

He remained at the hospital for three years until 1998 when a second psychological evaluation deemed him sane and he was released on the condition that he pay $50 bail and report to police monthly. 

Of course, Lopez never reported to the police. In fact, no one really knows where he is to this day. The last known sighting of Pedro Lopez was by his own mother, who he visited in his hometown of El Espinal. When he arrived at her house, his mother was sure that Pedro was there to kill her. Instead, he told her to get down on her knees and he gave her a blessing. 

In 2002, the Colombian government launched an Interpol order of arrest against Lopez for a fresh murder. Rumors say that he’s currently living in Tolima Department in Colombia as a homeless man. Others say that the relatives of his victims put a bounty on his head and he was murdered. No one really knows. You may have even walked past the world’s “most prolific serial killer” on the street and had no idea.