(NewsNation) — The parents of Connor Sturgeon, the 25-year-old man who opened fire at a Louisville bank, killing five people and injuring several others, are speaking out about their son’s mental health struggles.

In an interview with NBC’s “Today” show, Sturgeon’s parents revealed their son had been struggling with mental health issues and had been receiving treatment from a psychiatrist.

Lisa and Todd Sturgeon said their son’s mental health struggle began a year earlier with panic attacks, anxiety and a suicide attempt, but he was seeing a psychiatrist and taking medication, “Today” reported.

Lisa Sturgeon said her son, called her April 4, six days before the shooting at the Old National Bank in the city’s downtown. He said a panic attack forced him to leave work, and he thought he should take time off for a while.

Lisa Sturgeon said they had lunch the day after he called, and she set up a psychiatrist appointment and joined him there.

“We thought he was coming out of the crisis,” Lisa Sturgeon said.

The next morning, Lisa Sturgeon said her son’s roommate called saying Connor told him by phone: “I’m going to go in and shoot up Old National.” She called 911 but her son was already at the bank.

Police said Connor Sturgeon bought the AR-15 assault-style rifle used in the attack at a local dealership on April 4, the same day that Lisa Sturgeon said he told her about the panic attack. He killed five coworkers while live streaming the incident before police fatally shot him.

In an interview with the Courier-Journal, Sturgeon’s parents said that they hope their son’s tragedy will bring attention to the need for better mental health care.

“We hope that our son’s story will help others who are struggling with mental health issues,” said Sturgeon’s mother.

The Sturgeons expressed their sorrow in the “Today” interview, saying, “We are so sorry. We are heartbroken. We wish we could undo it, but we know we can’t.”

The shooting at the Old National Bank shocked the community and raised questions about gun violence and mental health.

While Sturgeon’s parents say that their son’s mental health issues were a factor in the shooting, they also acknowledge that the availability of guns played a role.

The Sturgeons said their son shouldn’t have been able to buy the rifle because of his mental state. They have been told that their son, who was seeing two mental health professionals, was able to walk into the store and walk out with the weapon and ammunition in 40 minutes, Todd Sturgeon said.

“If there had been a delay or something of that nature,” Lisa Sturgeon said to “Today.” “That would have been helpful.”

The Associated Press contributed to this report.