A former classmate said that Sturgeon was popular and smart and earned the nickname “Mr Floyd Central” in high school as his father was a coach on the basketball team.

After high school, Sturgeon went on to attend the University of Alabama to study finance.

While a student in Alabama, he detailed his struggles with self-esteem and making friends.

In a 2018 university essay for the university, Sturgeon wrote about his plan to “improve myself as a whole”.

“My self-esteem has long been a problem for me,” he wrote.

In recent years, there has been a greater awareness of a link between athletes who suffer concussions – in particular football players – and CTE.

CTE is a brain disease caused in part by repeated traumatic brain injuries, including concussions and non-concussive impacts, according to the Boston University CTE Center.

Symptoms of CTE can appear years after the sufferer is dealt repeated blows to the head and can include mood and behaviour problems including aggression and depression.

One especially notable example is that of Aaron Hernandez, the former New England Patriots tight end who was convicted of murder. After his death by suicide, researchers found he had severe CTE.

While it remains unclear if Connor Sturgeon suffered from the condition, a former classmate spoke of his shock at what the 25-year-old went on to do.

“I know everyone always says this about shooters but I truly would have never expected it to be him,” he said.

The nature of the gunman’s mental health struggles was not revealed but it comes after a former classmate revealed that Sturgeon experienced “multiple concussions” as a high school athlete – raising questions about whether he could have suffered from Chronic Traumatic Encephalopathy (CTE).

Sturgeon grew up in Indiana and attended Floyd Central High School in Floyds Knobs, where he was a star athlete playing basketball, football and running track.

The classmate told The Daily Beast that Sturgeon suffered so many concussions while playing football that he wore a helmet on the basketball court.

“The big thing I keep going back to is that in the first year of high school, we played football together in eighth grade, he was out most of the year because he had multiple concussions,” said the former classmate, who did not want to be named.

“Then he had a couple more in high school.”

The classmate said he wondered if his injuries were linked to Monday’s shooting.

“I’m not saying it’s the cause but I always think back to that… There were times I’d wonder, will this catch up with him? But never in this way,” he said.

“He’s the last person I’d expect would do this.”

Max Schachter lost his son Alex during the 2018 Parkland school shooting in Florida.

On Tuesday night, he reacted to the statements by Louisville Mayor Craig Greenberg, who said during a press conference that the bank shooter’s gun is likely to be auctioned off to the public under current Kentucky law.

“The thought of the Parkland murderer’s AR 15 that he used to kill Alex and 16 others being sold at auction to the highest bidder makes me want to throw up. They should fix this!” Mr Schachter said.

Texas state Senator Roland Gutierrez tweeted on Tuesday that “transparency is once again shown in wake of another tragic #massshooting. Yet @TxDPS has not released any footage from #Uvalde almost 11 MONTHS LATER. Their murderer is dead, just like the #Nashville & #Louisville murderers are. Give these families the closure they DESERVE. Let them know the TRUTH”.

On 24 May 2022, 19 students and two teachers were killed in a shooting at Robb Elementary School in Uvalde, Texas. Seventeen were injured.

The family of the gunman said in a statement that “while Connor, like many of his contemporaries, had mental health challenges which we, as a family, were actively addressing, there were never any warning signs or indications he was capable of this shocking act.”

The family said that they are cooperating fully with investigators in the case as they try to piece together what led up to the horror attack.

“While we have many unanswered questions, we will continue to cooperate fully with law enforcement officials and do all we can to aid everyone in understanding why and how this happened,” they said.

The family’s attorney also revealed that Sturgeon sent a final text message to his family before he opened fire in the bank.

“I love you,” it read.

The parents of the mass shooter who killed five colleagues in a Louisville bank on Monday have broken their silence to condemn their son’s “senseless acts of violence”.

While Sturgeon did struggle with his mental health, his family said there were no warning signs to suggest what he would go on to do.

“No words can express our sorrow, anguish, and horror at the unthinkable harm our son Connor inflicted on innocent people, their families, and the entire Louisville community,” the statement, shared by the family’s attorney, read.

“We mourn their loss and that of our son, Connor. We pray for everyone traumatized by his senseless acts of violence and are deeply grateful for the bravery and heroism of the Louisville Metropolitan Police Department.

Louisville Mayor Craig Greenberg called for a change in the way confiscated guns are handled. He criticised the state laws and added: “My administration has already taken action to remove the firing pin before turning confiscated guns over to the state. Because that’s all that the current law allows us to do.”

He said, during a press conference on Tuesday: “Under current Kentucky law, the assault rifle that was used to murder five of our neighbours and shoot at rescuing police officers will one day be auctioned off.”

“Think about that. That murder weapon will be back on the streets.”

The mayor of Louisville, Kentucky, Democrat Craig Greenberg, slammed the state’s gun laws during a press briefing after the bank shooting that left five dead.

Mr Greenberg was speaking on Tuesday after Monday’s assault on Old National Bank in downtown Louisville.

“To those in the national media that are joining us here today, this may be even more shocking than it is to those of us locally who know this and are dealing with this,” Mr Greenberg said.

“But under current Kentucky law, the assault rifle that was used to murder five of our neighbours and shoot at rescuing police officers will one day be auctioned off. Think about that,” he added.

“That murder weapon will be back on the streets one day, under Kentucky’s current law,” he said. “My administration has already taken action to remove the firing pin before turning confiscated guns over to the state. Because that’s all that the current law allows us to do.”