Officials said tests showed high concentrations of arsenic found in the bodies of the three people who died after eating the cake

Before three people died from eating a homemade Christmas cake believed to have been laced with arsenic, other family members noticed an off-putting flavor, authorities said, according to a recent news report.

Tatiana Denize Silva dos Anjos, 43, Maida Berenice Flores da Silva, 58, and Neuza Denize Silva dos Anjos, 65, all died after eating the homemade Brazilian Christmas cake called Bolo de Natal in Torres, Brazil, on Dec. 23 , local outlets including O Globo and GZH reported, citing police.

Three others, including Zeli Terezinha Silva dos Anjos, 61, who is thought to have baked the cake, and a 10-year-old boy, fell ill, the outlets report. The identity of the third person is unclear. 

The boy was discharged from the hospital on Friday, Jan. 3, but Zeli remains in the ICU in stable condition, per O Globo.

During a press conference on Monday, Jan. 6, Brazilian police official Marcos Veloso said that family members detected a “spicy” and “unpleasant” taste when eating the cake, CBS News reports.

Just one day earlier, authorities arrested Zeli’s daughter-in-law, identified only as “Deise,” on suspicion of triple homicide and triple attempted homicide, the local outlets reported, citing police.

Brazilian news outlet G1, citing officials, reported that the suspect allegedly searched “arsenic” and similar terms on Google prior to the incident. Officials said tests showed high concentrations of arsenic found in the fatal victims’ bodies and that the source of the poison was in the flour used to bake the cake.

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According to the World Health Organization (WHO), arsenic “is naturally present at high levels in the groundwater of several countries,” but “is highly toxic in its inorganic form.”

The three deaths have since prompted police to reopen an investigation into the death of Zeli’s late husband, Paolo Luiz. His death from food poisoning in September wasn’t investigated because it was considered natural, O Globo previously reported.