Upon receiving a report regarding the initial homicide, the Prevention Service of the Homicide Department dispatched members of the Judiciary Police to the scene, where they were taken aback by the sheer brutality of Maria Valentina's murder. The remains were subsequently examined by forensic expert Jose Sombreirero, who stated that in his 30 years of experience and 40,000 autopsies, he had never encountered anything of this nature.

The investigation that followed uncovered that the victim, known as Tina since childhood, was either involved in prostitution or struggled with drug addiction. Throughout 1992, the authorities received numerous anonymous calls and letters concerning the murder, all of which were investigated but yielded no substantial evidence.

On January 27 of the subsequent year, the assailant struck again, claiming the life of Maria Fernanda, whose body was discovered by railway workers. A full police brigade was deployed, and there was a consensus that the same individual was responsible; the body exhibited similar mutilations, with specific organs removed and found in close proximity to the previous crime scene.