The irony of Dmitriy Nikitin's death stunned friends and colleagues across the country. After a career of helping save lives, Nikitin died at the hands of a disgruntled patient in a killing that remains as senseless as it is unexplained. The patient, identified Friday as 53-year-old Nelson Flecha of Orange City, shot Nikitin in a parking garage at Florida Hospital's main campus on Thursday evening. Detectives were still sorting through evidence to pinpoint a motive in the slaying. Flecha targeted Nikitin, hunting down the doctor in the parking garage before turning the gun on himself. Police say the suspect lived alone in a working-class apartment off of U.S. Highway 17-92 in the south end of Orange City. Flecha's family told police he was a patient of Nikitin, police spokeswoman Lt. Barbara Jones said.