Authorities say the trouble developed around 8:30 a.m. April 10 at an Old National Bank office on East Main Street.
Police Chief Jacquelyn Gwinn-Villaroel told an afternoon briefing that the shooter, identified as Connor Sturgeon, 23, livestreamed the attack. The attacker was shot and killed by officers at the scene.
Sturgeon worked at the bank. A radio station reported Sturgeon graduated from Floyd County High School in 2015.
WHAS-AM, a separate news outlet, reported some people hid in a vault during the shooting spree. It noted everyone who died in the attack were Old National Bank executives.
At the afternoon briefing, Louisville Mayor Craig Greenberg called it "targeted violence." Greenberg noted he survived an assassination attempt as he campaigned for mayor last year.
One of the officers was in critical condition at a hospital after being shot in the head. He graduated from the police academy only 10 days earlier.
The afternoon briefing revealed two other people are in critical condition as well.
"This is awful. I have a very close friend who didn't make it today," Beshear told a news conference. He named that person later, saying Tommy Elliott "helped me start my law career.
“Please pray for all of the families impacted and for the city of Louisville," Beshear wrote in a tweet. He added that two of the people killed in the attack were personal friends.
The bank is located in a mostly-vacant downtown building, across the street from a minor league baseball stadium.
Louisville had another deadly mass shooting in September 1989. Former employee Joseph Wesbecker killed eight people at the Standard Gravure printing company and injured 12 others before killing himself.
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