Volume 28
Pedro Alonso López: The Monster of the Andes

Volume 28 · Chapter 4

The Monster of the Andes

Pedro Alonso López

Ambato, Ecuador, with killings also in Peru and Colombia 3 photos

Case at a glance

When
Late 1970s to 1980; arrested in 1980
Where
Ambato, Ecuador, with killings also in Peru and Colombia
Perpetrator
Pedro Alonso López
Outcome
Sentenced in Ecuador in 1980 to 16 years, released in 1994; released from a Colombian psychiatric hospital in 1998; whereabouts unknown since 1999

The case

Pedro Alonso López was born in 1948 in Tolima, Colombia, and said he was thrown out of the family home as a small boy. By his own account he began killing girls in Peru in the late 1970s, then moved through Colombia and Ecuador, taking children from markets and roadsides.

In March 1980, in the Ecuadorian market town of Ambato, a vendor screamed when she saw a stranger leading her daughter, about ten, away from the stalls, and the crowd held him for police. Soon afterward floodwater near the town exposed the bodies of four girls. López said nothing until officers planted an undercover policeman in his cell for weeks; he then boasted of murders in three countries and offered to show them the graves. He led them to the remains of 53 girls, and claimed over 300 in all. Ecuador’s maximum sentence then was 16 years, and that is what he got.

Released in August 1994 after 14 years, López was handed to Colombia to face a charge over a child’s murder. A court found him not criminally responsible and committed him to a psychiatric hospital. In February 1998 doctors declared him sane, and he walked out after posting a small bond. He renewed his identity card in Bogotá in 1999. In 2002 Colombia sought him through Interpol over another child’s death. No confirmed sighting has been reported since.

From the book

Read the full story

This case is told in full in True Crime Case Histories, Volume 28 by Jason Neal.

Get Volume 28 on Amazon

Case photographs

3 photos
Pedro Alonso López interviewed in prison
Pedro Alonso López interviewed in prison
Pedro Alonso López, “the Monster of the Andes”
Pedro Alonso López, “the Monster of the Andes”
Pedro Alonso López mugshots
Pedro Alonso López mugshots

Where it happened

Ambato, Ecuador
Ambato, where López was arrested in 1980 · Open in Google Maps

Why this case

“I usually avoid cases where the body count is the whole story, but this one is really about the system that let him go. A man who admitted to more than a hundred murders served fourteen years and was released on a promise to check in monthly. Readers should watch the paperwork, not the monster.”

— Jason Neal, author of True Crime Case Histories

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About the author

Jason Neal writes the True Crime Case Histories series, which has covered hundreds of real cases from the United States and around the world since 2019. Each volume collects twelve cases, researched from court records, police reports and news coverage. jasonneal.com

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