NASHVILLE, Tenn. -- Angry parents and students congregated at the Tennessee State Capitol on Thursday advocating for gun reform in the wake of Monday's mass shooting at a private Christian school in Nashville.
Former "Bachelorette" star Ali Fedotowsky, a Nashville resident and a mom of two, was among the protesters, writing on Instagram, "This morning was extremely emotional and powerful. Nashville wants change!!!!"
"I will scream and shout and cry until I have nothing left!" she wrote. "I want my children to live and I want your children to live."
And on Wednesday evening, hundreds of people gathered at a candlelight vigil to mourn and honor the three children and three staff members killed at Covenant School.
Local, state and federal officials along with dignitaries, religious leaders and community figureheads attended the somber ceremony at One Square Park in the downtown section of Tennessee's capital city. First lady Jill Biden and singer-songwriter Sheryl Crow were among those in attendance, though Biden did not address the crowd.
Various speakers took turns reading aloud the names of the victims and expressing condolences to the grieving families.
"Just two days ago was our city's worst day," Nashville Mayor John Cooper told the crowd. "I so wish we weren't here, but we need to be here."
After the shooter opened fire at the school Monday morning, responding officers shot and killed the suspect about 14 minutes after the initial 911 call came in, according to the Metropolitan Nashville Police Department.
In one dramatic 911 call, a woman told the dispatcher she was hiding in an art room closet. She said she could hear the gunshots and pleaded with responders to hurry. At one point she whispered to someone else in the closet to stay quiet.
Police have identified the slain children as 9-year-old students Evelyn Dieckhaus, William Kinney and Hallie Scruggs. The adult victims were identified as 61-year-old custodian Mike Hill, 60-year-old head of school Katherine Koonce and 61-year-old substitute teacher Cynthia Peak.
During Wednesday's vigil, a former local school administrator, Tricia Drake, said she couldn't stop thinking about her last conversation with Koonce, who she said had advised her on how to best prepare for an active shooter scenario.
"My last conversation with her, in August, was about who she used for her active shooter training because I know that she would have researched somebody," Drake told ABC News in a tearful interview. "We ended up using the same active shooter training at the school where I was also a head. I can't believe that was my last conversation with her."
Drake said she knew Koonce had made her mark when she saw the footage that police released from two of the responding officers' body-worn cameras. One of the videos shows a Covenant School staff member meeting Officer Rex Engelbert at the school's main entrance, telling him: "The kids are all locked down, but we have two kids that we don't know where they are." She then is seen using a key to unlock the door so officers could go inside.
"Students were in their classrooms, locked up, the professional outdoors to lead the Metro policeman. She had a key, what her headcount was, she knew exactly where the students would be, she was prepared," Drake told ABC News. "I'm sure they had run those drills, and it's because of Katherine and the foresight she had to make sure her staffers were prepared."
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Drake, who declined to say the name of the Nashville school she used to work for, said she underwent the same active shooter training that Koonce used and that the key is to adopt a "warrior mentality," accepting injury rather than death. Part of the training, she said, is to throw students out of windows and run away as far as possible. Drake said she believes Koonce's preparations saved lives on Monday.
Drake also recalled the moment she realized something might be seriously wrong when news about the shooting at the Covenant School began to spread.
"I texted my sister and friends of mine to say: That's Katherine's school. I know she's going to come out. She's going to come out anytime now and tell everybody that it's under control, that everything's ok," Drake recounted. "And I waited like everyone else for Katherine to come out and I thought it was so strange that she was not visible. She was so professional, so prepared, so committed to her faculty and those sweet children of hers, and it's just such a loss. It is unthinkable that this has happened in our little town."
House Speaker Kevin McCarthy broke his silence on the shooting at his Thursday news conference, arguing that passing legislation alone is not the answer.
"I don't think that a piece of legislation would solve this. I think a nation together, working together, solves a problem that's much bigger than us," he said.
McCarthy said the country needs to have a "severe conversation" about mental illness.
"We have got to deal with mental illness. We got to see what's driving individuals to think you would go to innocent children, a Christian school, to shoot in," he said.
The suspect -- identified as Audrey Hale, 28, of Nashville -- was a former student of the Covenant School, according to police. Metropolitan Nashville Police Chief John Drake told reporters on Tuesday that it appears the school was likely targeted, but "students were randomly targeted."
The police chief had told reporters on Monday that Hale was female and identified as transgender but didn't immediately provide more details. A police spokesperson later told ABC News that the suspect was assigned female at birth but pointed to a social media account linked to Hale that included the use of the pronouns he/him.
The suspect was armed with two assault-style rifles, a handgun and "significant ammunition" at the time of the attack, according to police. Investigators have since searched Hale's home in Nashville, where they seized "a sawed-off shotgun, a second shotgun and other evidence," police said in a press release on Monday.
The police chief said the suspect had legally purchased seven guns from five different local stores and hid some of those weapons at home. Hale was under a "doctor's care for an emotional disorder," the police chief said, and Hale's parents "were under the impression that was when she sold the one weapon" they believed Hale owned.
Hale also had a detailed map of the school as well as "writings and a book we consider to be like a manifesto," the police chief told ABC News in an interview Tuesday on "Good Morning America."
"We have not been able to determine a motive as of yet," he added. "The investigation is very much still ongoing."
Video from the school's surveillance cameras shows the suspect arriving in a vehicle and parking in the parking lot at 9:54 a.m. ET. Minutes later, the suspect is seen shooting through a door on the side of the school and entering the building. Hale allegedly went from the first floor to the second floor, firing multiple shots, according to police.
Police received a 911 call about an active shooter at the school at 10:13 a.m. ET. As officers responded to the scene, the suspect fired on police cars from a second-floor window, police said.
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Video from two of the responding officers' body-worn cameras shows them entering the school, following the sound of gunfire to the second floor and finding the suspect in a lobby area near a window. After an officer shouts "reloading," officers Rex Engelbert, a four-year veteran, and Michael Collazo, a nine-year veteran, both fire at the suspect.
The Covenant School, a private Christian school for children in preschool through sixth grade, has about 209 students and 40 to 50 staff members. It does not have a school resource officer, according to police.
In a statement released Monday night, the Covenant School said its community "is heartbroken."
"We are grieving tremendous loss and are in shock coming out of the terror that shattered our church and school," the school said. "We are focused on loving our students, our families, our faculty and staff and beginning the process of healing."
ABC News' Libby Cathey, Vera Drymon, Alex Faul, Matt Foster, Ben Gittleson, James Hill, Doug Lantz, Molly Nagle, Olivia Osteen, Lauren Peller, Darren Reynolds and John Santucci contributed to this report.