Lissa María Caiza is an Ecuadorian woman convicted of three separate killings in and around Pifo, a rural parish on the northeastern edge of Quito, during 2020. In August 2021 a court in Pichincha province found her guilty of murdering her two children, aged nine and five, on the night of October 27, 2020, and sentenced her to 34 years and eight months, the maximum aggravated term. In April 2022 another trial court convicted her of murdering Jaime Geovanny Yanchaguano, 28, whose death prosecutors placed in the days before the children's, and added 22 years. In July 2023 a third court convicted her of murdering Marco Escanta, a co-worker, in June 2020, and imposed another 22 years.
Police in Quito called her a possible serial killer within two weeks of her arrest, and the city's popular press gave her the name "Doña Veneno." Officers also accused her of poisoning several relatives and other people who survived. None of those allegations had come to a verdict by 2026, and a psychological assessment cited by the newspaper Extra in 2021 disputed the serial-killer label.
In 2020 Caiza was in her mid-twenties. Police gave her age as 25 that November, and Vistazo gave it as 28 in July 2023. She lived in Pifo with her two children. She was separated from their father, and court reports describe him as her former partner. Prosecutors later presented chat messages between the two as evidence.
Her working life left little trace beyond one fact: she and Marco Escanta were co-workers at a flower-export company, Vistazo and Teleamazonas reported. A neighbor told Extra in November 2020 that she had befriended Caiza only twelve days before the deaths, had talked with her for long stretches while the two children played nearby, and had noticed nothing unusual. Caiza told her she had a bad temper. The same neighbor said she was the first person to come to the family's aid in the early hours of October 28.
The children have never been publicly named. A relative quoted by Extra described them as affectionate and innocent, and said they loved to play together. "Now they are little angels in heaven," the relative said. They were buried side by side in the cemetery at Yaruquí, a neighboring parish.
Marco Escanta was 48 and lived with his wife and children in the Florida de Chantag neighborhood of Pifo. A local neighborhood leader told Extra he had been a good and cooperative neighbor. According to the prosecution case later accepted in court, he and Caiza were together on June 11, 2020, and he died in Pifo that day.
At first his death was not treated as a homicide. General Fausto Olivo, head of the national violent-deaths police directorate, Dinased, later said Escanta had died of intoxication. Investigators had lifted a fingerprint in the case. The case went no further until the following November, when police compared that print with prints taken in the October investigation and found they matched Caiza's. "On comparing the two events, of June and October, we reached this conclusion," Olivo told reporters.
Escanta's wife and two of their children fell ill the next day after consuming something in the home that, according to the prosecution, had been contaminated with the same substance. They were taken to hospital and survived. His wife told Extra that she had always believed Caiza killed her husband.
Jaime Geovanny Yanchaguano was 28, according to the court reports of his case. Police described him as a close friend of Caiza's; Vistazo and the Cuenca newspaper El Mercurio, citing the prosecution, described him as her former partner. His family lived in Checa, another rural parish northeast of Quito.
According to an account his family gave Extra in November 2020, he left home on October 18, 2020, after stopping to ask his mother's blessing. Within hours a sister received a message from Caiza saying he had been kidnapped by drug traffickers who wanted $8,000 for his release. The family reported him missing on October 20. Further messages lowered the demand to $4,000, and later claimed he owed Caiza $1,200 for building work. The last contact, on October 25, threatened legal action over that debt. The family came to believe the messages were meant to hide what had already happened. EFE and Vistazo, reporting the prosecution case in 2021, gave October 25 as the date of the missing-person report, and Vistazo's report of the April 2022 verdict gave October 18.
Iván Naranjo, head of the violent-deaths unit for the Quito district, told Extra in late October 2020 that investigators believed Yanchaguano had died five or six days before the children. At the charging hearing in his case in May 2021, prosecutors placed his death between October 18 and October 24, 2020. His body was found in Pifo early on October 28, during the police response to the children's deaths.
On the night of October 27, 2020, the prosecution said, Caiza poisoned her two children in Pifo and then took a toxic substance herself. The appeal court later placed the events at about eight in the evening.
That night she telephoned the children's father. He testified that she told him she had written him a letter and that she would take with her what was hers, meaning the children. In a chat between them, presented at trial through an audio and video expert report, she threatened to kill herself and take the children with her. At about two in the morning on October 28 she called him again, said she felt ill after swallowing a toxic substance, and asked for help. Neighbors alerted police that she had collapsed. About an hour later an officer told the father to come to Pifo, where he learned that his children were dead.
Caiza was taken first to the hospital at Yaruquí and then to a hospital in Calderón, in northern Quito, where she was treated and survived. A woman Caiza had hired to look after the children had started work that same day. She too was poisoned, police said, and was treated in the same hospitals and recovered.
On October 29, 2020, prosecutors charged Caiza with murder at a flagrancy hearing held at the hospital, and a judge ordered her held in preventive detention. She was later taken to the Centro de Rehabilitación Social de Cotopaxi, the prison at Latacunga in Cotopaxi province. Prosecutors began a separate investigation, run by the same unit, into Yanchaguano's death.
Fingerprints on three glasses collected in the October investigation were attributed to Caiza. In the first days of the investigation, police also told Extra that they planned a psychiatric evaluation, and Olivo said investigators might be dealing with "a possible psychological disturbance."
On November 6, 2020, Dinased held a press conference in Quito. Olivo said investigators had found "a relationship with an earlier homicide by poisoning," meaning Escanta's death in June, through the fingerprint match. Carlos Perugachi, head of criminalistics for the Metropolitan District of Quito, said technical and scientific work had established her possible involvement in the crimes, which he classed as serial murders and attempted murders, with poisoning as the common method. Naranjo said all of the killings and attempts had taken place within her family and social circle.
Police also described a family gathering in Pifo on September 2, 2020, at which, they said, Caiza had tried to poison relatives. Naranjo spoke of nine relatives in all, including her mother and siblings. Eight of them recovered, he told Teleamazonas, while her mother was left seriously ill. EFE, reporting the same briefing, said police alleged she had tried to poison two brothers and her 56-year-old mother. Police further alleged that on October 5 she had tried to kill a woman who came to her home asking for work.
Initial medical tests, police said, found no sign that Caiza had taken any substance before the deaths, so investigators presumed she had acted fully conscious. She was held for 30 days while the investigation continued. Naranjo later told Extra that he saw in her conduct signs of what he called criminal psychopathy. A forensic psychologist quoted in the same article cautioned that only a proper evaluation could show whether she had that profile, and Extra noted that if she were found guilty she would be the first woman in Ecuador to be counted as a serial killer. The previous case it cited was that of Luis Taipe, known as the "scarf killer," in 2010.
In December 2020 the family of José Luis Erazo, 42, a friend of Caiza's, told Extra they believed she was responsible for his death too. He had died in Checa about a month before the October deaths. An autopsy attributed the death to a heart attack. His relatives said that after the funeral Caiza sent them messages claiming she knew who had killed him, asking them to repay money she said she had lent him, and claiming to be pregnant with his child.
Valeria Mena, a lawyer acting for the family, said an expanded toxicology test had found that he was poisoned, and the family announced it would file a complaint with prosecutors. No charge in Erazo's death had been reported by May 2026.
On December 22, 2020, Caiza appeared by video from the Latacunga prison, in an orange uniform, at the hearing that would decide whether she stood trial for her children's deaths. The prosecutor, Elba Garzón, read the letter Caiza had left for the children's father. Extra described it as part self-justification and part reproach. "I don't expect you to forgive me, I know you hate me," it said, "and now you will hate me even more." She wrote that she had given her children the love she had been denied, and that she would never leave them with him.
Garzón told the court that Caiza had said to a psychiatric examiner, "I wanted my children to die too." The prosecution also presented autopsy findings of violent death, forensic examination of her phone, and hospital records showing that the older child, who had a chronic illness, had been admitted in September and October and that doctors had linked the October crisis to poor handling of the medication at home. A psychiatric evaluation, the prosecutor said, found no mental illness but persistent thoughts of suicide.
The defense argued that the children had died of accidental, natural asphyxia that their mother had not caused. Judge Ximena Rodríguez rejected that argument and sent the case to trial.
The trial began at the Complejo Judicial Norte in Quito in May 2021, with Caiza again appearing by video. On its second day the forensic doctor Margarita del Valle testified that she had found no trace of poison. She detected traces of the virus that causes Covid-19 but said it had not caused their deaths. Her conclusion was homicidal mechanical asphyxia, and she was clear that the deaths were violent.
The trial was suspended in May while prosecutors formally charged Caiza in the Yanchaguano case, and resumed later in the year. Caiza's defense then argued that the children had died of Covid-19, an illness they had already had and recovered from. The prosecution's experts ruled that out. The autopsy and a histopathology examination found that the deaths were violent homicides, involving asphyxia and intoxication by a substance that had not been identified. A psychological evaluation found that she had been oriented in time and place when the crime was committed. In that evaluation she denied killing her children. Staff from the hospitals that treated her also testified.
On August 3, 2021, when the trial resumed, a Tribunal de Garantías Penales of Pichincha found Caiza guilty as the perpetrator of murder, applied aggravating circumstances, and sentenced her to 34 years and eight months in prison. The court ordered her to pay $20,000, the equivalent of a thousand basic salaries, in reparation to the children's father, and ordered psychological care for him. EFE's report of the verdict noted that she was still under investigation for another homicide.
Her defense appealed, arguing that the judgment was poorly reasoned because the evidence was insufficient and nothing in law established either the crime or her responsibility. Garzón, by then of prosecutors' Unit No. 6 for persons and guarantees, defended the trial evidence: the findings of the forensic doctor and the histopathology expert, a toxicology report showing that the children had taken a toxic substance, and the expert report on the chat with the children's father.
In March 2022 the criminal chamber of the Provincial Court of Justice of Pichincha unanimously rejected the appeal and confirmed the sentence in full. "There is no doubt that the children died from violent, homicidal causes," the chamber said, as quoted by El Mercurio. A later cassation appeal was also rejected, Extra reported in 2026, leaving the conviction final.
The charging hearing in Yanchaguano's death was held on the morning of May 6, 2021, while the children's trial was suspended. The judge accepted the prosecution's request for a three-month investigation and kept Caiza in preventive detention. According to Fiscalía, the cause of death was asphyxia. Valeria Mena, who also represented the Yanchaguano family, said tests had shown an unidentified substance in his system and that this had left him unable to defend himself. She said it seemed strange to her that Caiza had acted alone, though she offered no theory of an accomplice.
On April 14, 2022, Vistazo reported that a Tribunal de Garantías Penales had found her guilty as the direct perpetrator of Yanchaguano's murder under article 140, numeral 2, of the Código Orgánico Integral Penal, which carries 22 to 26 years. The court imposed 22 years. The forensic doctor's findings, as reported, were asphyxia and intoxication by a substance still to be determined. The evidence included testimony from his sister, a technical report on the audio and video of Caiza's conversations with his relatives, including the kidnapping claim and the $8,000 demand, and a forensic psychologist's evaluation of Caiza. No appeal in that case was reported.
Prosecutors from Pichincha's Unit No. 2 for persons and guarantees brought the June 2020 death to trial in 2023. On July 19, 2023, Vistazo and Teleamazonas reported that a Tribunal de Garantías Penales had unanimously accepted the prosecution's case and convicted Caiza of murdering Escanta, under article 140, numerals 2 and 3, of the penal code, covering a victim left defenseless and the use of poison. The sentence was 22 years.
The evidence included her fingerprint, the toxicology results, the testimony of the forensic doctor who carried out the autopsy, and the police officers who attended. Vistazo reported that three members of his household were also poisoned and survived. Teleamazonas put Caiza's total at four deaths, counting her children.
Caiza has been held at the Centro de Rehabilitación Social de Cotopaxi, near Latacunga, since late 2020. In 2022 she was given a further four months for bringing prohibited items into the prison, Vistazo and Teleamazonas reported. By July 2023 she was serving sentences for three murder convictions and that offense.
In January 2026 her lawyers filed a new challenge in the children's case. It sought no reduction of the prison term. Instead it targeted the $20,000 reparation owed to the children's father. Because there appeared to be no specific appeal against such a payment, the filing was entered as an appeal on costs. It was assigned to a specialized criminal chamber, which was to decide whether to admit it. When Extra reported the filing on May 3, 2026, no decision had been published, and Caiza remained in prison in Cotopaxi.
Several people the police counted as intended victims survived and spoke to the press. The woman hired to look after the children told Extra in June 2021 that she had forgiven Caiza, had left the matter "in the hands of Jehovah," and did not plan to press charges for the attempt on her life. Another woman, who had been interviewed for the same job a few days earlier but did not start, told Extra she believed she would otherwise have been the first to fall ill.
Escanta's widow, who was herself hospitalized, said she had always believed Caiza was responsible for her husband's death. Yanchaguano's sister testified at his trial. The children's father testified about the calls of October 27 and 28 and was awarded the reparation that Caiza's lawyers were still contesting in 2026. The family of José Luis Erazo, through their lawyer, said they wanted the maximum sentence the law allowed.
How the children died. The prosecution described poisoning from the start, and the appeal court cited toxicology findings. At trial, however, one forensic doctor testified that she found no poison and gave the cause as homicidal mechanical asphyxia, and the autopsy findings accepted by the court combined asphyxia and intoxication by an unidentified substance. The courts found the deaths to be homicides either way. The defense theories, first accidental asphyxia and then Covid-19, were rejected.
Whether she is a serial killer. Dinased officers used the term in November 2020, citing the fingerprint link to the June death and a common method. A psychological analysis described by Extra in June 2021 found that the killings of her children and of Yanchaguano were not directly connected, and that there was no careful planning, ritual or sense of power or gratification. On that basis, Extra wrote, she would not fit the profile of a serial killer. The courts have since convicted her of three killings committed on separate occasions.
The other poisonings. The September 2020 family gathering, the October 5 visitor and the woman hired as a carer were described by police and prosecutors as attempted killings. The press counts varied, from nine relatives to thirteen or sixteen people in all, and none of these allegations had led to a reported conviction by May 2026.
The Erazo death. His family's belief that Caiza poisoned him rests on their own account, her messages to them and a toxicology result described by their lawyer. The autopsy gave a heart attack as the cause, and no charge had been reported.
Details about Yanchaguano. Reports gave his age as 26, 27, 28 and 35, and his relationship to Caiza as friend, partner and former partner. The court reports of 2022 give 28 and former partner. The date his family reported him missing appears as October 18, 20 or 25.
June 11, 2020: Marco Escanta, 48, dies in Pifo; his death is not at first treated as a homicide.
September 2, 2020: Police later allege that Caiza tried to poison relatives at a family gathering in Pifo; police say eight of them recover.
October 5, 2020: Police later allege an attempt on a woman who came to her home seeking work.
October 18, 2020: Jaime Yanchaguano leaves his family's home in Checa; messages claiming he has been kidnapped follow within hours.
October 18 to 24, 2020: Period in which prosecutors place Yanchaguano's death.
October 20 to 25, 2020: His family reports him missing; ransom and debt messages continue to October 25.
October 27, 2020: The woman hired as a carer is poisoned and survives. That night Caiza's two children, aged 9 and 5, are poisoned in Pifo.
October 28, 2020: The children and Yanchaguano are found dead; Caiza is taken to hospital.
October 29, 2020: Charged with murder at a hospital hearing; preventive detention ordered.
November 6, 2020: Dinased links her by fingerprints to Escanta's death and describes her as a possible serial killer.
December 2020: The Erazo family says it will file a complaint over his death.
December 22, 2020: Judge Ximena Rodríguez sends her to trial for the children's murders.
May 2021: Trial opens; on May 6 she is formally charged in the Yanchaguano case.
August 3, 2021: Convicted of murdering her two children; 34 years 8 months and $20,000 reparation.
March 2022: Provincial Court of Justice of Pichincha unanimously rejects her appeal.
April 2022: Convicted of murdering Jaime Yanchaguano; 22 years.
2022: Sentenced to four months for bringing prohibited items into prison.
July 2023: Convicted of murdering Marco Escanta; 22 years.
January 2026: Her lawyers file a challenge to the $20,000 reparation order.
May 2026: She remains in prison in Cotopaxi; no decision on the filing reported.