RIO DE JANEIRO, April 3 (Xinhua) -- Law consultant Alexandre Nardoni pleaded not guilty on Thursday to the murder of his five-year-old daughter Isabella, who was thrown out of a window on the sixth floor of an apartment building in Sao Paulo last weekend.

    A local court on Wednesday ordered the arrest of Nardoni, 29, and his wife Anna Carolina Jatoba, 24, the child's stepmother, as suspects in the case.

    Nardoni on Thursday released a letter saying he has been treated "like a monster" since his daughter died.

    "Everyone judges me without even knowing me. I would never do that to anyone, especially to my daughter," Nardoni said in the letter.

    According to Nardoni, he took Isabella up to the family's apartment first on Saturday evening, and then left the girl alone for a few moments while he went downstairs to help his wife bring in his two younger children, who were waiting in the car. When they returned, they found Isabella lying unconscious on the building's ground floor.

    Forensic analysts ruled out an accident, as the child's body bore signs of physical aggression and the window was protected by a safety net, which had been torn. Blood spots were also found in the apartment's bedroom where the child had been.

    In his defense, Nardoni argued that someone else was in the apartment that evening, probably a burglar, and that he saw such a person, but did not see his or her face.

    However, neighbors told police they heard the girl scream "daddy" that evening, as if a fight was going on in the apartment.

    Other pieces of evidence implicate Nardoni in the investigation. Isabella's biological mother had reported him to police for threatening Isabella and her mother some years ago. Additionally, his ex-wife has recently filed a request for an increase in their child's alimony, with which he disagreed.