(NewsNation) — The parents of the man accused of killing 10 people at a Buffalo grocery store are not under criminal investigation by the local prosecutor, he confirmed Monday to “NewsNation Prime.”

“The parents are not on my radar right now as far as any criminal activity,” Erie County District Attorney John Flynn said. “The parents are on my radar right now as to what they can shed on the defendant. And in the course of that investigation, if anything arises on the parents, I will advise the proper authorities.”

However, Flynn said he could not speak for any investigations that might be underway in the defendant’s Conklin, New York home in Broome County.

“If any conduct occurred in Broome County, then that would be a Broome County matter,” he said.

Flynn also confirmed there was an “alleged incident” involving the defendant at his school a year ago. Reportedly, he threatened to open fire, but the matter was closed after a hospital evaluation.

“I’m in the process now of drilling down on exactly what happened,” Flynn said. “I’m not drilling down to blame anyone in Broome County. I’m drilling down to figure out what was going through his mind and whether or not he had any intentional thoughts about coming to Buffalo back then.”

Flynn also said the defendant’s 100-page manifesto is an important part of establishing his intent.

The community is still reeling after the attack, which is being investigated as a hate crime because investigators believe the gunman targeted Black people. President Joe Biden is expected to visit Buffalo on Tuesday.

The next step in the investigation is a court hearing Thursday, which the defendant could waive, and then convening a grand jury.

Flynn said more charges besides the violence could be coming.

“My main focus is on the legality of the gun,” he said.

Flynn also told NewsNation that a man, 52, was arrested after allegedly phoning in copycat threats to a local pizza restaurant and a local brewery. He’s facing felony terrorist threat charges.