Police said the shooting took place at the beginning of the work day inside the Fifth Third Bank building, a 30-storey tower that sits above bustling Fountain Square a few blocks from Great American Ball Park and the riverfront along the Ohio River.
A Cincinnati city council official said there had been "fatalities" with police warning of an "active shooter".
An ongoing investigation has provided no indication of the shooter's motive, according to Isaac, but "mental health issues" may have been a factor, he said.
Leonard Cain told The Enquirer he was going into the bank when someone alerted him about the shooting.
Lexington Mayor Jim Gray tweeted: "Concerning today's shootings, we offer our condolences to Mayor John Cranley, the victims and good citizens of Cincinnati".
The local Telugu Association of North America office said they plan to help Kandepi's father.
"It is a very horrific situation".
Fox19 also quoted a Fifth Third bank manager about the scene.
Hamilton County Prosecutor Joe Deters said the rapid police response probably prevented many more casualties.
Police cordoned off a portion of the city's downtown.
Austin is grateful for the officers who aided her and for the support from many others, the spokesperson said.
Almost three hours after the incident, several streets in downtown Cincinnati remained closed to traffic.
The other two victims were identified as Luis Calderon, 48, and Richard Newcomer, 64, a contractor who worked for Gilbane Building Company.
"I looked behind me and saw the guy - he shot and then he shot again", Michael Richardson told the Enquirer.
Reports indicate that during the shooting, there was an exchange of gunfire between law enforcement and the suspect in the lobby and the loading dock of the bank. Two other people were shot, but they survived.
Omar Enrique Santa Perez, 29, shot three people to death before he was fatally shot by police officers in a brief gunbattle.
A police spokesman says two victims were treated at UC Medical Center.
Witnesses in the area described a chaotic walk to work, hearing about 10 gunshots ring out during the morning rush.
The building is located in Fountain Square, a hub for entertainment and dining in the city.
"It could have been any one of us", Cranley said. He did not hear the shots, he said, but he saw emergency responders wheeling out victims on stretchers. We knew immediately something was wrong.
"I was walking past the Chipotle and I had my headphones in when some woman stopped me and said 'You don't want to go to the square, we just heard gun shots, ' " he says.