Has Mexico City found its much-sought-after “dog killer”?

For the past month, the residents of one of Mexico City’s most upscale neighborhoods have been searching for a killer.

They have been looking for the person who was behind a rash of poisonings at a nearby park in Condesa. The victims: dogs of all breeds, some wearing expensive collars and other accessories bought by their owners.

The suspect would mix rat poison with food leftovers and plant the venomous concoctions in the dog park

The suspect would mix rat poison with food leftovers and plant the venomous concoctions in the dog park area of Parque México, for the unsuspecting animals that ran and played in one of the city’s most popular green spots.

In just four days, 19 dogs were reported dead.

After a month-long search, prosecutors announced that they might have their suspect: a 75-year-old woman who is reportedly fed up with the mess the animals were leaving in her garden.

In videos taken by residents and local security teams, an elderly woman can be seen putting out food near the dog park area along Ozuluama street.

“There are images of her throwing something in the area where the pets ate material that made them sick and died,” a source at the Mexico City’s prosecutor’s office told a local newspaper.

The female suspect, who has still not been arrested, also lives in the Condesa neighborhood, according to officials.

Authorities, who do not want to release her name, fear that she could become the victim of an attack, given that a local organization is offering a $5,000 reward for the culprit.

Under Mexico City’s Penal Code, anyone convicted of animal cruelty could face up to two years in prison.

“A person of her age could ask for house arrest, and nothing will happen to her,” said Gilberto Zamora of the prosecutor’s environmental crimes unit.

A group of neighbors, who have organized themselves and created a Facebook page Cuidando nuestros perritos (Taking care of our puppies), have come up with a psychological profile of a suspect capable of carrying out such a slaughter of animals.

“We believe we are facing an individual with a sadistic and psychopathic personality based on the choice of poison, dosage, variety and quantity of food found, as well as the repeated and defiant way it was left out,” the group said.

Veterinarians found traces of zinc phosphate and strychnine in three of the dog corpses

Neighbors also say that the poison is a hazard to the children who play in the park, which is one of the safest in the Mexican capital.

Pet owners tried to save their animals by inducing vomiting but after a few minutes the dogs would undergo convulsions before succumbing.

Veterinarians at Mexico’s National Autonomous University (UNAM) found that that the bodies of three dogs had high levels of zinc phosphate – commonly used in rat poisoning – and strychnine, a controlled substance regulated by the Federal Commission for Health Risk Protection (Cofepris).

Mexico City officials have tried to calm residents by cleaning up the area and assigning additional security.

On Sunday, dozens of neighbors held a protest – without their pets – demanding that authorities resolve the case.

“Not one more dog!” they shouted, hoping that the suspected “dog killer” will finally be brought to justice.

English version by Martin Delfín.