The gunman who killed three people at a Dollar General store in Jacksonville, Florida, on Saturday had earlier been turned away from the campus of a historically Black university -- just blocks away from the site of the shooting that targeted Black people, authorities said.
The shooter, described by police as a White man in his early 20s, first went to the campus of Edward Waters University, where he refused to identify himself to an on-campus security officer and was asked to leave, the university stated in a press release.
"The individual returned to their car and left campus without incident. The encounter was reported to the Jacksonville Sheriff's Office by EWU security," the school said.
The university, which is in a historically Black neighborhood, went into lockdown Saturday and students living on campus were told to stay in their residence halls.
The suspect, who has not been publicly identified, put on a bulletproof vest and mask while still on campus before he went to the nearby Dollar General, Jacksonville Sheriff T.K. Waters told CNN's Jim Acosta.
Armed with an AR-15 style rifle and a handgun, the gunman opened fire outside the store and then again inside, fatally shooting the three victims before killing himself, according to Waters.
Authorities have not publicly identified the victims, described as two males and one female, all of whom are Black, the sheriff said.
Investigators are now probing the gunman's motives, history with law enforcement calls and how he obtained the firearms, Waters said, adding what is clear is that the attack targeted Black people.
"This shooting was racially motivated, and he hated Black people," Waters said at a news conference Saturday evening.
The suspect left behind writings to his parents, the media and federal agents that outlined his "disgusting ideology of hate" and used racial slurs, the sheriff told reporters. It didn't appear that the shooter knew the victims and it is believed the shooter acted alone, he said.
"There is absolutely no evidence that the shooter is part of any large group," he added.
"This is a dark day in Jacksonville's history," the sheriff said. "Any loss of life is tragic, but the hate that motivated the shooter's killing spree adds an additional layer of heartbreak."
The FBI has launched a federal civil rights investigation into the shooting and "will pursue this incident as a hate crime," said Sherri Onks, special agent in charge of the FBI's Jacksonville office.
The Jacksonville attack marked one of several shootings reported in public places in the US over two days, including near a parade in Massachusetts and at a high school football game in Oklahoma.
There have been at least 470 mass shootings in the US so far in 2023, according to the Gun Violence Archive. Like CNN, the archive defines a mass shooting in which four or more people are wounded or killed, not including the shooter.
The nation surpassed the 400 mark in July -- the earliest month such a high number has been recorded since 2013, the group said.
Shooter's father called police after shooting started
The shooter, who lived in Clay County with his parents, left his home around 11:39 a.m. Saturday and headed to Jacksonville in neighboring Duval County, Waters told CNN.
At 1:18 p.m., the gunman texted his father and told him to check his computer, according to Waters, who did not provide details on what was on the computer.
At 1:53 p.m., the father called the Clay County Sheriff's office, the sheriff said.
"By that time, he had began his shooting spree inside the Dollar General," Waters said of the gunman. Officers responded to the scene as the gunman was exiting the building.
"He saw them, he retreated back inside the building and went into an office," where he shot himself, Waters said.
Photos of the weapons the gunman had were shown by authorities, including one firearm that had swastikas drawn on it. While it remains under investigation whether the gunman purchased the guns legally, the sheriff said they did not belong to the parents.
"Those were not his parents' guns," Waters told reporters Saturday. "I can't say that he owned them but I know his parents didn't -- his parents didn't want them in their house."
"The suspect's family, they didn't do this. They're not responsible for this. This is his decision, his decision alone," the sheriff later told CNN.
Gunman's history and access to guns being probed
The shooter was the subject of a 2017 law enforcement call under the state's Baker Act, which allows people to be involuntarily detained and subject to an examination for up to 72 hours during a mental health crisis.
Waters did not provide details on what led to the Baker Act call in that case, but said normally a person who has been detained under the act is not eligible to purchase firearms.
"If there is a Baker Act situation, they're prohibited from getting guns," he told CNN. "We don't know if that Baker Act was recorded properly, whether it was considered a full Baker Act."
The shooter's writings indicated he was aware of a mass shooting at a Jacksonville gaming event where two people were killed exactly five years earlier, and may have chosen the date of his attack to coincide with that anniversary, Jacksonville Mayor Donna Deegan said.
Florida Gov. Ron DeSantis on Saturday condemned the shooting and called the gunman a "scumbag."
"He was targeting people based on their race. That is totally unacceptable. This guy killed himself rather than face the music and accept responsibility for his actions, and so he took the coward's way out. But we condemn what happened in the strongest possible terms," DeSantis said, according to a video statement sent to CNN by the governor's office.
The US Department of Homeland Security is "closely monitoring the situation," Secretary Alejandro Mayorkas said in a statement on Saturday.
"Too many Americans -- in Jacksonville and across our country -- have lost a loved one because of racially-motivated violence. The Department of Homeland Security is committed to working with our state and local partners to help prevent another such abhorrent, tragic event from occurring," he said.
