Authorities in São Paulo, Brazil, are investigating the mysterious deaths of a mother and daughter who reportedly died after eating a suspected poisoned cake, as police press for the arrest of the man believed to have delivered it.

The victims, Ana Maria de Jesus, 52, and her daughter Larissa de Jesus Castilho, 21, fell gravely ill after eating the cake in July 2025.

Both were rushed to the hospital but could not be saved.

According to investigators, the cake was allegedly delivered by a man identified as Leonardo, the husband of Ana’s niece, Patricia.

Police now consider him the prime suspect and have requested his arrest — a motion reportedly denied by a judge for reasons not yet disclosed.

Toxicology reports revealed traces of pesticides in the victims’ bodies, raising strong suspicions of poisoning.

During the investigation, detectives examined the couple’s phones and discovered a troubling series of online searches, including phrases such as “heart attack causes convulsions” and “intoxication from cleaning products.”

Authorities suspect that the motive may be linked to a financial dispute, as Ana was known to have regularly lent money to her niece and her husband.

CCTV footage allegedly captured Leonardo arriving at Ana’s residence on his motorcycle to deliver the cake. Shortly after consuming it, Ana called her daughter, complaining of severe illness and an inability to stand.

Ana was admitted to Heliopolis Hospital, where doctors placed her on a ventilator. Later that day, Larissa also ate some of the same cake and collapsed soon afterward. Both women later died.

The São Paulo Secretariat of Public Security confirmed that homicide detectives are leading the investigation.

“On October 8, search and seizure warrants were executed, resulting in the confiscation of cell phones for data extraction. Investigators are still analyzing the information obtained,” the Secretariat stated.

The investigation, which began following the deaths in late July, remains active as police continue gathering evidence to determine whether the pair were deliberately poisoned and to bring those responsible to justice.