Four dead, including gunman, in US bank shooting

Police and fire officials investigate following a shooting nearby in the Fifth Third Bank building in Cincinnati, Ohio. (Mark Lyons/Getty Images/AFP)

Gun shots rang out just after 9.00am (9.00pm Singapore time) at the high-rise headquarters of Fifth Third Bank, a regional financial institution in Ohio's third-largest city.

Five people were shot, some multiple times, and one victim died at the scene while two others succumbed to their injuries in hospital.

Police identified the gunman, felled in a shootout with officers, as 29-year-old Omar Perez. He was not immediately determined to have any connection to the bank, according to detectives.

"There may be a possibility that there's some mental health issues involved here," Cincinnati police chief Eliot Isaac told a news conference, cautioning that the investigation was in its early stages.

Police believe Perez was armed with some 200 rounds of ammunition and a legally-bought 9mm semi-automatic handgun when he entered the lobby of the 30-story building, Isaac said.

Several officers arrived within minutes of the first emergency calls and four of them shot the suspect, killing him at the scene.

The building the gunman targeted was said to have strict security, and it wasn't clear how he was able to get in.

"Per Fifth Third Bank, the shooter was not an employee of Fifth Third," police spokeswoman Tiffaney Hardy told AFP via email.

'GROTESQUE VIOLENCE'

The quickly-responding police were credited with preventing widescale carnage.

"This is clearly an act of grotesque violence to innocent people and it should frighten all of us," said Cincinnati Mayor John Cranley.

"It has happened too much around this country and we, as a country, have to figure out how to end it."

Witnesses told local media they heard as many as 20 gunshots.

One unnamed construction worker told WLWT television that he saw two victims being brought out in the aftermath, including one woman in a blood-soaked shirt.

"I just (saw) people running out of the building," the witness said.

"There are guys with suits laying on the ground, hiding behind big flower pots," he said.

'A SENSELESS ACT'

Bank employees sheltered in situ for an hour or more as officers swept the building and cordoned off several downtown city blocks.

"There was a senseless act of gun violence on the streets of Cincinnati this morning," Ohio Governor John Kasich said on Twitter.

"I commend the law enforcement, fire and (emergency medical) personnel who swiftly responded to the scene and share my deepest sympathies with the innocent victims of this violent attack."

It was the latest in more than 200 mass shootings in the US this year alone, with previous incidents often leading to mostly fruitless calls for gun control reforms.

In June, a gunman killed five and injured two at The Capital Gazette newspaper offices in Annapolis, Maryland.

"It is all too clear that we have to do more in Ohio to address the gun violence affecting communities across the state," said a statement from the Ohio chapter of Moms Demand Action for Gun Sense.