CNN
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Louisville is set to host a vigil Wednesday to let community members grieve the five people killed this week in a downtown bank shooting, as the public absorbs fresh details that investigators are releasing about how the massacre unfolded.

The vigil comes a day after police released dramatic police body camera footage of Monday’s shooting at Old National Bank, in which authorities say a 25-year-old employee opened fire on his colleagues and then engaged in a shootout with police before he was shot dead.

The attacker, livestreaming the gruesome assault online, killed five of his coworkers around 8:30 a.m. in Kentucky’s most populous city, about 30 minutes before the facility was to open, authorities said. Several others were hospitalized, including a rookie police officer who was shot in the head and was in critical condition Tuesday.

“Our city is heartbroken,” Louisville Mayor Craig Greenberg told CNN’s Wolf Blitzer on Tuesday evening. “These five victims should not be dead – just like everyone else who was killed by gun violence in our city, in our country, should not be dead.”

It’s still not clear what provoked the shooter to go on the deadly rampage. As an investigation continues, officials expect to release audio Wednesday of 911 calls about the shooting, the mayor said.

And the city will hold a vigil at 5 p.m. Wednesday at the Muhammad Ali Center in Louisville, the mayor said.

The vigil will “acknowledge the wounds, physical and emotional, that gun violence leaves behind,” Greenberg told reporters Tuesday. “It will be an interfaith opportunity for our entire community to come together – to grieve, to heal, to begin to move forward.”

On Tuesday, Louisville police released bodycam video from the officers who responded to yet another mass shooting in the US.

The public footage begins with a video from Officer Nickolas Wilt – a 26-year-old rookie who’d graduated from a police academy just 10 days prior – who drove up to the scene with his training officer, Cory “CJ” Galloway.

As Wilt ran toward the gunshots that officers faced upon arrival, Wilt was shot in the head, police said. The released version of Wilt’s footage cuts off before he is shot.

Body camera footage from Galloway shows him taking fire, and then retreating to a safe position behind a planter as officers talk about how they can’t see the gunman, and that the gunman is shooting through windows in the front of the bank. At some point, Galloway was also shot.

The shooter eventually broke the bank’s lobby glass windows, giving officers vision on his location, Deputy Chief Paul Humphrey said.

Galloway shot and killed the gunman, Humphrey said.

The entire situation – from when the gunman began firing his assault weapon to when he was killed by police – lasted for about nine minutes, according to Louisville police Lt. Col. Aaron Cromwell.

Those killed in the shooting were Joshua Barrick, 40; Juliana Farmer, 45; Deana Eckert, 57; Tommy Elliott, 63; and James Tutt, 64, police said.

Nine people – including Eckert, before she died Monday – were hospitalized after the shooting, officials said. Among the eight current survivors, five had been discharged as of Tuesday, a hospital spokesperson said.

The three victims who remained hospitalized Tuesday include Wilt, who underwent brain surgery and was in critical condition, and two others who were in fair condition, the hospital spokesperson said.

Monday’s massacre in Louisville was one of at least 147 mass shootings this year in the US, according to the Gun Violence Archive, which like CNN defines a mass shooting as four or more people shot, not including the shooter.

It took the assailant one minute to complete the bloodbath before he stopped and waited for police to arrive, according to footage of the massacre described by a city official to CNN.

The shooter, identified by police as 25-year-old Connor Sturgeon, had livestreamed the gruesome attack on Instagram – the video has since been taken down.

The Instagram video begins by showing an AR-15-style weapon, followed by a worker in the bank saying good morning to the gunman, the official said.

The gunman then tries to shoot her in the back but fails because the safety is on and the weapon still needs to be loaded, the official said. Once the shooter loads the weapon properly and takes the safety off, he shoots the worker in the back, the official said.

The assailant then continues his rampage, firing at workers while they tried to outrun him, the official said. The shooter does not go to other populated floors of the bank, the official said.

Once the shooter finishes firing, he sits in the lobby area that looks out onto the street, apparently waiting for police, the official said.

Police arrive about a minute and half later, the official said, at which point a gunfire exchange ensues before police eventually shoot and kill the gunman.

Sturgeon had interned at the bank for three summers and been employed there full-time for about two years, his LinkedIn profile showed. The assailant had been notified that he would be fired from the bank, a law enforcement source said Monday.

The mayor, however, said he doesn’t believe the shooter was given a notice of termination.

“From what I have been told from an official at the bank, that is not accurate,” Greenberg told reporters Tuesday.

Sturgeon used an AR-15-style rifle in the shooting, police said. Six days before the killings, he legally purchased the rifle from a local gun dealership, the interim Louisville police chief said Tuesday.

Staff members were holding their morning meeting in a conference room when the gunman opened fire, bank manager Rebecca Buchheit-Sims told CNN.

She said the massacre “happened very quickly.” Buchheit-Sims attended the staff meeting virtually and watched in horror as gunfire exploded on her computer screen.

“I witnessed people being murdered,” she told CNN. “I don’t know how else to say that.”

A former high school classmate of Sturgeon’s who knew him and his family well said he never saw any “sort of red flag or signal that this could ever happen.”

“This is a total shock. He was a really good kid who came from a really good family,” said the classmate, who asked not to be identified and has not spoken with Sturgeon in recent years. “I can’t even say how much this doesn’t make sense. I can’t believe it.”