A man allegedly stabbed his best friend and brother-in-law to death before fleeing the scene with the victim’s wife.
Igor Peretto was found dead in his sister’s flat with more than 20 stab wounds to his body on Saturday (31 Aug).
Police found the apartment in disarray with a bloodied knife in the bathroom and the 27-year-old victim lying on the bedroom floor.
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The prime suspects include Igor’s wife, Rafaela Costa da Silva, his sister, Marcelly Peretto and her husband, Mário Vitorino da Silva Neto.

After turning herself in, Marcelly reportedly told the police that her co-suspects were having an affair.
Her lawyer Felipe Pires de Campos claims she was in another room when her estranged husband allegedly stabbed Igor, with whom he owned a car dealership, to death.
Local media report the killing was preceded by a blazing row ignited by Igor’s suspicions that his wife was having an affair with Mário.

One line of investigation suggests Rafaela abandoned her young son to run away with him.
The police say there were signs of a struggle at the crime scene in Praia Grande, Brazil.
CCTV footage reportedly shows Marcelly arriving at the home with Igor’s wife, Rafaela Costa da Silva, in the early hours.
Mário and Igor are also captured on the camera an hour later.
During the escape, Mário is believed to have forced Marcelly into a car before leaving her at a petrol station and then picking up Rafaela.
Mário and Rafaela are also believed to have withdrawn 100,000 BRL (£13,500) from his and Igor’s joint business account
The pair may have driven towards Rio de Janeiro with a police hunt currently underway, as reported by Need To Know.

The victim was laid to rest in nearby Santos on Sunday (1 Sep).
He leaves behind two sons.
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