Transcript for Police in Arizona are working to stop an apparent killing spree

Next the widening murder investigation inarizona, and erns about a possible killer on the loose. Phoenix police zeroing in on the homicide of a well-known forensic psatrist, connected he jonbenet ramseyase back in thes. Stigators on the lookout of this man intch, wanted in the doctor's dead fatal ootings of at least two more people in scda ABC's Marci goez picks up that story. Rte tonight, police I Arizona working to stop an apparentng, searching thect who shot and killed renowned forensicologist Steven Pitt outside his phoeni case to the shooting death of two paralegals near their office in ot, day, and trying to detne if another homicide today is also linked. His offender is soe's neighbor, they are someone's Frie Reporter: Igators say uhether the first victim, Pitt, was ted for his hifile work. Consultingcases including E death of jonbenet Ramsey in 1996 and on the Jodi Arias ial. Witnesses saying they hearttarguing loudly Witman around 5:30 Thursday evening, fall by gunshots. Police releasing this sketch O the suspect, tonight, aing the ic for help solving these cases. Ice think they H a murder on hands going on a mass killing SP if there connec the question why, and who is next. Monzalez joins us now. Marci, I understand you have some more reporting tonight on thirst shooting involving famed forensic psychiatrist? Reporter: That's right, Tom. Ation in phoenixts that Pitt may have known his killer, and pol say, two womere not killed at random. Tonight, investigators are sti working to pie these together.tom? Marci gonza for us tonight. Marci, thank you.

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