Police say the man who shot and killed three people in a racially motivated attack in Florida wrote about his hatred of black people.
Ryan Christopher Palmeter, 21, fired eleven shots at a woman who was sitting in her car in Jacksonville, before walking into a store and shooting two other people.
Sheriff TK Waters said he then shot himself.
Mayor Donna Deegan said the attack was motivated by racial hatred.
At a news conference Sunday, Sheriff Waters confirmed that the gunman had no prior criminal history and was living with his parents in Clay County.
The three victims have been identified as Anault Laguerre Jr., 19, Gerald Deshon-Gallion, 29, and Angela Carr, 52.
The company said Laguerre was working at the Dollar General store where the attack took place.
Police said the gunman wrote letters detailing his hatred of black people.
“Accurately: This shooting was racially motivated and it was hateful to black people.” Sheriff Waters said.
“He knew what he was doing. He was 100 percent clear,” he added. He added, “He knew what he was doing and, again, it’s disappointing that anyone would go to such lengths to harm another person.”
Mr Waters said the gunman was held for 72 hours in 2017 under the Baker Act, mental health legislation that allows for the involuntary detention of an individual for treatment.
But the sheriff said his weapons were obtained legally and told reporters the problem was not the availability of weapons, but the killer being a “bad guy”.
He urged people not to “seek logic in senseless acts of violence”.
Jacksonville police showed video from surveillance cameras at the press conference showing the moment the attacker got into the car and killed the first woman. A video was then cut of him entering the store.
Waters also confirmed that the gunman allowed some people to exit the store without being injured.
“Why? I don’t know. Some of them were white, but I think there was a couple who weren’t,” he said.
On Sunday, US Attorney General Merrick Garland said the Justice Department was “investigating this attack as a hate crime and an act of racially motivated violent extremism.”
“No person in this country should live in fear of violence fueled by hate, and no family should grieve the loss of a loved one because of bigotry and hate,” he said.
The attack took place less than a mile from the historic Edwards Waters University.
The university said in a statement that the gunman first went to the university campus, where a security officer asked him to identify himself. When he refused, he asked him to leave.
“The individual returned to his car and left the university campus without any incident,” the statement added.
Sheriff Waters said the gunman was then seen wearing a bulletproof vest and mask before leaving campus.
The university was closed after the shooting.
