A fourth fatal shooting in a Phoenix suburb on Saturday may be linked to three other slayings, including the killing of a prominent forensic psychiatrist who assisted in high-profile murder cases such as the JonBonet Ramsey homicide, according to police.

The Scottsdale Police Department said they received a call about a man who had been found fatally shot inside an office located in a business complex that houses mostly therapists and counselors.

The man killed Saturday was Marshall Levine, a psychologist and counselor, Karen Kolbe, who rented him office space, told the Arizona Republic.

The possible fourth killing comes after authorities linked three fatal shootings over two days.

The first victim was identified by authorities as Steven Pitt, a forensic psychiatrist who worked on the high-profile investigation into the killing of 6-year-old JonBenet Ramsey, a beauty pageant star who was found dead at her family’s home in Boulder, Colorado. Ramsey’s murder, which remains unsolved, attracted national attention. A prosecutor cleared her parents and brother in 2008 based on DNA evidence.

Pitt was killed Thursday outside his office, police say. Besides the JonBenet Ramsey case, he also worked on the “Baseline Killer” serial murder case in the early 2000s, FOX 10 reported.

Witnesses questioned after the Pitt killing said they heard arguments preceding loud gunshots, describing the suspect as an “adult male, bald and wearing a dark-colored hat with a short brim.”

Police released a sketch of the suspect in the three killings.

The other two victims were paralegals, identified as Veleria Sharp, 48, and Laura Anderson, 49. They were fatally shot at a law office on Friday.

“We don’t know the relationships or the connections,” Scottsdale Police Spokesman Sgt. Ben Hoster told the Associated Press Saturday.

One woman managed to escape the building but died after being transported to a hospital. The other woman was found dead at the scene, the Phoenix New Times reported.

“Our investigation has determined that this double homicide is related to the shooting of Steven Pitt on May 31, 2018, in Phoenix,” Scottsdale police said in a statement.

The website of Burt/Feldman/Grenier, the law firm that employed Sharp and Anderson, says it practices divorce, child support and other aspects of family-law litigation and mediation.

Sharp and Anderson’s law firm issued a statement saying: “Laura has worked with us as family for more than ten years,” while “Veleria was a treasured member of our work family. She brought joy, calmness, warmth and compassion to all that she did.”

Police have notified the family members of the victims, but do not believe they are in any danger. “We’re asking the public to remain vigilant and to call us if they notice anything out of the ordinary,” Hoster said.