RENO, Nev. (AP) -- Police think a suicidal gunman was on a mission of violence when he calmly entered a third-floor urology office and opened fire with a 12-gauge shotgun, killing one doctor, shooting another and critically wounding a third victim.
A witness who was among those the shooter passed in the waiting area where the attack took place told The Associated Press on Wednesday that the man could have killed many more people at the Reno medical complex if that was his intent.
Detectives have not been able to establish a motive or relationship between the man who shot the two doctors and the relative of a patient Tuesday before killing himself.
"But the fact the shooter went through the first and second floor, made his way to the third floor of the building, would indicate to me it is not a random event," Reno Deputy Police Chief Mac Venzo said. He said they don't know yet whether the gunman had been a patient of the urologist killed or knew any of the victims.
"While we piece this thing together, we are trying to figure out what that relationship is, if there is a relationship at all," he told reporters at police headquarters.
Venzo said they have tentatively identified the killer but were withholding his name because they've been unable to reach his next of kin. He said they have talked to 29 witnesses so far, with more interviews pending.
Police identified the slain doctor as Charles G. Gholdoian, 46, a urologist at Urology Nevada within the Center for Advanced Medicine on the campus of the Renown Regional Medical Center. In critical condition were a female doctor whose name has not been released and Shawntae Spears, the 20-year-old relative of a patient.
"Urology Nevada is shocked and saddened by the events that occurred," the center's statement said. "At this time we have no information as to why these terrible events occurred, and we are cooperating with the authorities in every way possible to learn more."
Dr. Michael Morkin, an emergency room surgeon and the incoming chief of staff at Renown where the victims were taken, said both doctors were his friends. He described them as "exceptional physicians."
"It is a very difficult time for the medical community," he told reporters.
Police say there were about 100 people in the office building when authorities were alerted at 2:05 p.m. Tuesday about an "active shooter."
Vitalis Ozoude, a state auditor, was in the reception area of Urology Nevada with his wife and 3-year-old son waiting for his child's appointment when the gunman walked in just before 2 p.m.
"He wasn't running or shouting or doing anything like that," Ozoude told the AP.
"He looked like he belonged," he said in explaining why the dozen or so people in the waiting room didn't immediately react to the sight of a man carrying a gun. "I thought he worked there, and he was just getting a gun from his car or taking it to his office."
Ozoude said the gunman was calm when he said something like "you better get out of here," and the receptionist then began telling everyone to "get out."
"I don't think he meant to kill everybody because if he did he had ample opportunity to do that," he said.
Ozoude said people ran from the office, and he and others went to the elevators, but he didn't hear gunfire.
At the third-floor urologist's office, the gunman went past the front desk armed with a shotgun and entered the patient examination rooms, Venzo said.
Moving through the exam area, he fired at least four rounds from the shotgun, striking three victims, before making his way back to the office's waiting area and turning the gun on himself, police said.
The shooting comes nearly two months after a 12-year-old boy opened fire at an area middle school, killing a math teacher before killing himself. Two victims from that attack were treated at Renown Regional.
The medical center also has treated victims of other recent tragedies, including a crash at a Reno air race in 2011 that killed 11 people and a shooting rampage at a Carson City restaurant the same year that killed three uniformed Nevada National Guard members.
Associated Press writers Sandra Chereb in Carson City and Michelle Rindels in Las Vegas contributed to this report.
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