Known as "Dr. Bumbum" - Brazilian slang for backside, Furtado was arrested at an office complex in Rio de Janeiro's Barra de Tijuca neighborhood. Police also arrested his mother, Maria de Fatima Barros, who worked with him.
Police said Furtado performed the buttock enhancement procedure on bank manager Lilian Calixto at his Rio home Saturday. Calixto fell ill during the procedure and Furtado rushed her to a nearby hospital, where she died hours later.
Police say the exact cause of her death has not been determined.
Furtado disappeared after he dropped Calixto off at the hospital and a judge issued a warrant for his arrest.
Inside a police station Thursday, Furtado told reporters he was innocent of any wrongdoing. "There was an occurrence with the patient," he said.
In a video aired by the G1 news portal, Furtado said, "A fatality has occurred - a fatality that could happen to any doctor." G1 said the video was posted on a social media site after Furtado's arrest.
The doctor's lawyer, Naiara Baldanza, said in a statement that "any conclusion regarding the death of Lilian Calixto and my client's responsibility in this fatality is premature."
Associated Press journalists Beatrice Christofaro and Yesica Fisch contributed to this report.
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