Louisville police said the gunman who killed five people and injured eight others at a bank on Monday had purchased the rifle legally a week before the shooting on April 4.
"He purchased the weapon legally from one of the local dealerships here in Louisville," said Louisville Metro Police Chief Jacquelyn Gwinn-Villaroel.
Police on Monday identified the shooter as 25-year-old Connor Sturgeon. He was an employee at Old National Bank, who, according to a CNN report knew he was about to be fired.
Authorities have not yet released a motive in the shooting, but described the attack as "targeted." Sources told CNN that the gunman had written a suicide letter to his parents and a friend, though it remains unclear whether the note was seen before or after the shooting. He livestreamed the attack on Instagram, but the video has since been deleted.
Rep. Morgan McGarvey, who represents Louisville in Congress, confirmed with reporters on Tuesday that the shooter had also "texted or called" at least one person about his intent to die by suicide.
Louisville Metro Mayor Craig Greenberg, a Democrat, slammed Kentucky's government for loose gun laws, calling on lawmakers to give Louisville autonomy in passing its own gun reform laws to prevent future tragedies.
"This is happening in America everywhere and will keep happening until we say 'enough' and take meaningful action," he said. "Doing nothing is not a strategy, is not a solution."
Per Kentucky law, the rifle used in the attack will eventually be auctioned to the public, the mayor said.
Kentucky is one of 26 U.S. states that allow for eligible adults to carry a firearm without the need for a permit. In 2019, the state also removed any provision requiring adults to pass a background check if they plan on carrying and concealing a weapon. Beyond a federal law that restricts felons from purchasing weapons, the state has no law prohibiting people with mental health disorders from purchasing weapons.
Four victims were pronounced dead at the scene on Monday, and authorities later said they were all employees at the bank. Police identified them as Thomas Elliott, 63, Josh Barrick, 40, Jim Tutt, 64, and Juliana Farmer, 57. Deana Eckert, 57, later succumbed to her injuries at a local hospital.
The shooter was killed by responding officers, police said on Monday.
Elliott, a senior vice president at Old National Bank and a longtime Democratic fundraiser, was a close friend of both Greenberg and Kentucky Gov. Andy Beshear.
Of the other eight victims who were hospitalized, two remain in the intensive care unit and another two are being treated for non life-threatening injuries, a doctor from University of Louisville hospital said on Tuesday.
One of those victims in the ICU is Officer Nickolas Wilt, 26, who was shot in the head and remains in critical condition.
The Louisville shooting marks the 146th mass shooting in the U.S. this year, and comes just two weeks after another shooting killed six people, including three children, at a private school in Nashville, Tenn.