(CNN) -- Police arrived "to a very chaotic scene, with victims and witnesses running everywhere" at a FedEx Ground facility near Indianapolis' main airport late Thursday night, where a former employee shot and killed eight people and wounded others, an Indianapolis police official told CNN.
Indianapolis police on Friday afternoon identified the gunman as 19-year-old Brandon Hole, who was last employed by FedEx in 2020, said Deputy Chief Craig McCartt.
Vice President Harris and I have been briefed on the mass shooting at a FedEx facility in Indianapolis. God bless the eight individuals we lost and their loved ones, and we pray for the wounded for their recovery.— President Biden (@POTUS) April 16, 2021
We can, and must, do more to reduce gun violence and save lives.
This is another heartbreaking day and I’m shaken by the mass shooting at the FedEx Ground facility in Indianapolis. Indiana State Police are working with local responders and we will continue to offer any and all resources needed to assist during this tragedy. 1/3— Governor Eric Holcomb (@GovHolcomb) April 16, 2021
We are deeply saddened by the senseless loss of life that occurred at a FedEx facility in Indianapolis overnight. We offer our deepest condolences and prayers for all affected, and await further details to determine what exactly happened and why.— Todd Rokita (@AGToddRokita) April 16, 2021
IMPD Detectives Investigate Shooting Involving Multiple Victims https://t.co/3aG1pQagTl— IMPD (@IMPDnews) April 16, 2021
This morning, Indianapolis residents are confronted with the horrific news of yet another mass shooting, an act of violence that senselessly claimed the lives of eight of our neighbors.— Mayor Joe Hogsett (@IndyMayorJoe) April 16, 2021
I am heartbroken by the mass shooting at the FedEx facility here in Indianapolis and praying for all affected by this tragedy. I am communicating with local authorities to get all details of the attack and my office stands ready to help everyone affected any way we can.— André Carson (@RepAndreCarson) April 16, 2021
Maureen and I just learned of the tragedy in Indianapolis when we woke up. Our hearts are mourning for the individuals who’ve senselessly lost their lives, all of their loved ones, and their co-workers at FedEx who will be dealing with this tragedy for a long time to come.— Senator Mike Braun (@SenatorBraun) April 16, 2021
The shooting at FedEx was a senseless tragedy. Indiana and the nation mourn for the lives lost and forever changed last night.— Senator Todd Young (@SenToddYoung) April 16, 2021
Our nation grieves with the families who lost loved ones in Indianapolis and we pray that those who were wounded recover quickly. As I said last week, we’ve had more tragedy than we can bear and solutions to prevent gun violence exist. @POTUS and I urge Congress to act.— Vice President Kamala Harris (@VP) April 16, 2021
Authorities are holding a press conference right now. We are learning the suspect is 19-year-old Brandon Hole. They did confirm he was a former employee here and last employed in 2020 @WTHITV
— Sarah Lehman (@WTHISarahLehman) April 16, 2021
The gunman took his own life and police didn't fire, McCartt said.
Officials haven't released the names of victims.
The suspect was known to federal and local authorities, and a relative reached out to authorities warning about that person's potential for violence, according to three law enforcement sources briefed on the matter.
Investigators are trying to determine the motive and were searching what they believe is the gunman's home, FBI special agent in charge Paul Keenan told reporters late Friday morning.
"Nothing we learn can heal the wounds of those who escaped with their lives, but who will now ... endure the memories of this horrific crime," Indianapolis Mayor Joe Hogsett said at the same news conference.
The mass shooting is the country's deadliest since 10 people were killed March 22 at a grocery store in Boulder, Colorado.
Thursday night's killings began when a gunman "got out of his car, and pretty quickly started some random shooting outside the facility," McCartt said.
The gunman then "went inside and did not get very far into the facility at all," while shooting others there, McCartt told CNN earlier Friday.
Two employees inside the building at the time heard as many as 10 gunshots, they told CNN affiliate WISH. The men left the building and watched as about 30 police cars responded, they said.
"Thank God for being here because I thought I was going to get shot," one of them, Jeremiah Miller, told WISH.
News 10's Sarah Lehman spoke with D.J. Boyles. He's worked at the facility for around four years.
He told us he woke up around 3 am to dozens of calls and texts asking if he was alive and okay.
That's when he heard the news.
"It hurt me like, so like...it really shattered me because in those four, almost five years I've been able to make a family at FedEx with people who I love, and like, was able to joke around with and have a good time with while working at the same time. So to think someone actually did this blows me away," Boyles said.
Investigators have heard the shooting lasted "just a couple minutes -- that it did not last very long," McCartt said.
"My understanding is, by the time that officers entered ... the situation was over -- that the suspect took his life very shortly before officers entered the facility," McCartt told reporters.
Four people were found dead outside and four others, not counting the shooter, were dead inside, McCartt said.
The incident marks at least the 45th mass shooting in the United States since the Atlanta-area spa shootings on March 16. CNN considers an incident to be a mass shooting if four or more people, excluding the gunman, are wounded or killed by gunfire.
Several people wounded
Police have offered differing accounts of the wounded. McCartt said four survivors were taken to a hospital with gunshot wounds and a fifth was taken to a hospital with "some sort of injury" that he didn't specify.
In a news release, police said five people were taken to a hospital with gunshot wounds and two other people were treated at the scene and released.
The gunman had at least one weapon, which investigators believe was a rifle, McCartt told reporters.
Police early Friday were trying to make sense of the crime scene while relatives of FedEx employees gathered at a nearby hotel, which officials offered as a place where they could await news, reunite with the workers and meet with police chaplains.
"Many of the employees did not have cell phones on them in the facility," and so many survivors were not immediately able to contact their families, McCartt told CNN.
Several people tearfully embraced as they reunited Friday morning at the hotel, video from CNN affiliate WISH showed.
Sources: FBI looked into relative's warning
It's not clear when the suspect's family member warned authorities, but the outreach was followed up by local authorities and the FBI, according to the three law enforcement sources briefed on the matter.
The FBI opened a preliminary investigation into any possible threat, but it eventually closed the inquiry after concluding there wasn't sufficient evidence to continue it, according to the sources.
A spokeswoman for the Indianapolis Metropolitan Police Department declined to comment about CNN's reporting.
When asked Friday morning whether witnesses indicated that FedEx or security personnel had any indication that something like Friday's shooting would happen, McCartt said no.
"We're still working with FedEx security for anything that might have been an indication this was going to happen right now," McCartt said at the Friday morning news conference.
'They didn't sound like gunshots at first'
FedEx worker Timothy Boillat and his coworker heard what they thought initially were "two loud metal clangs" when the shooting started, he told CNN affiliate WRTV.
"They didn't sound like gunshots at first ... Then, we heard three more shots, and then my buddy ... saw someone running out of the building." Boillat said.
"And then more shots went off. Somebody went behind their car to the trunk and got another gun," Boillat said, without saying whether that person was the shooter.
"And then I saw one body on the floor," Boillat told WRTV.
Police are asking anyone who was at the scene and may have left for safety or for medical treatment to contact them to provide information on the shooting.
Governor and other officials offer condolences
Hogsett, the mayor, said the process of healing will be impacted in part by what conversations the nation has about cycles of violence "driven by readily accessible guns."
"We must guard against resignation or even despair -- the assumption that this is simply how it must be and that we might as well get used to it. We need the courage that compels courageous acts that push past weariness," Hogsett said.
FedEx released a statement saying it was "deeply shocked and saddened by the loss of our team members."
"Our most heartfelt sympathies are with all those affected by this senseless act of violence. The safety of our team members is our top priority, and we are fully cooperating with investigating authorities," FedEx said.
Indiana Gov. Eric Holcomb said Friday is "another heartbreaking day and I'm shaken by the mass shooting at the FedEx Ground facility in Indianapolis."
"In times like this, words like justice and sorrow fall short in response for those senselessly taken. Our thoughts are with the families, friends, coworkers and all those affected by this terrible situation," Holcomb said.
Flags will be lowered to half-staff from Friday until sunset Tuesday "in remembrance of those we've lost," Holcomb said.
President Joe Biden ordered flags at federal facilities to be lowered to half-staff and urged Congress to act on firearm legislation, calling gun violence an "epidemic."
US Rep. Andre Carson, whose district includes Indianapolis, tweeted that he was heartbroken by the mass shooting.
"I am communicating with local authorities to get all details of the attack and my office stands ready to help everyone affected any way we can," he said.
STATEMENT FROM INDIANA GOVERNOR ERIC HOLCOMB
“This is another heartbreaking day and I’m shaken by the mass shooting at the FedEx Ground facility in Indianapolis. Indiana State Police are working with local responders and we will continue to offer any and all resources needed to assist during this tragedy. In times like this, words like justice and sorrow fall short in response for those senselessly taken. Our thoughts are with the families, friends, coworkers and all those affected by this terrible situation.
"Today, I will order that flags be lower to half-staff from now until sunset on Tuesday, April 20 in remembrance of those we've lost."
STATEMENT FROM LT. GOV. SUZANNE CROUCH
"There are Hoosiers who will no longer be with us, and there are families who will never recover because of last night's senseless act of violence. My sincerest thoughts and prayers go to the families, friends and coworkers at the FedEx Ground facility in Indianapolis. I am thankful for our first responders who acted swiftly to come to the aid of Hoosiers, and I know our law enforcement officers at the local, state and federal levels will use all resources necessary while they work through this tragic event."
STATEMENT FROM FEDEX
"We are deeply shocked and saddened by the loss of our team members following the tragic shooting at our FedEx Ground facility in Indianapolis. Our most heartfelt sympathies are with all those affected by this senseless act of violence. The safety of our team members is our top priority, and we are fully cooperating with investigating authorities."