At a press conference Tuesday evening Louisville Metro Police Deputy Chief Paul Humphrey said the shooter who attacked the downtown offices of Old National Bank and killed four employees was laying in wait for police as they arrived.

First on the scene just three minutes after the 911 call was received, rookie Officer Nickolas Wilt and his training officer Cory C.J. Galloway came under fire in their vehicle as they arrived.

Video shows that the shooter had the tactical advantage of being above the officers in the lobby of the bank. Because of the type of glass on the bank lobby windows, the shooter also had the advantage of being able to see the officers while not being seen, Humphrey said.

Officer Galloway retrieved his AR-variant patrol rifle from the trunk of the patrol car and led Officer Wilt, who was armed with a duty pistol, up the step to the landing area of the lobby. The gunman fired on them, critically wounding Wilt and inflicting minor injury on Galloway, according to Humphrey.

Wilt went down with a shot to the head. Galloway rolled off the steps and behind a stone planter.

Tense minutes followed as Galloway tried to gain an angle to shoot the suspect and found he didn’t have one. The entire time he worried about Wilt trapped in the line of fire.

The shooter then broke out the glass of the lobby windows, which can be heard crashing to the floor on Officer Galloway’s body camera video. This gave Galloway a shot and he fired multiple rounds, killing the suspect.

As Galloway approached the downed gunman to ensure he was no longer a threat, other responding officers came to the aid of Wilt. The severely wounded officer was transported to the nearest hospital in the back seat of a police vehicle.

In an interview early Tuesday morning with WLKY , LMPD Interim Chief of Police Jacquelyn Gwinn-Villaroel said that his condition was stable and that he was looking better. He is still listed as critical.

Humphrey praised all of the officers and emergency personnel who responded to the scene. Multiple agencies were involved.

After the suspect was down, officers tended to the wounded. Humphrey said medical personnel had told him that the aid provided by the officers saved lives.

He also praised an LMPD lieutenant who drove a paramedic vehicle, so that the paramedics could render care to a wounded person in the back.

Humphrey reserved his highest praise for Wilt and Galloway. He said Galloway—who had been sworn in just 10 days before the attack—had no experience, but he had “training and character.”

“I would love to have either of these officers ride with me,” Humphrey said.