(CNN) The 18-year-old man accused of mass murder at a Buffalo supermarket legally obtained an AR-15 style rifle, believed to be the same weapon he described modifying in a lengthy, racist rant posted online before the attack.
Law enforcement officials told CNN on Tuesday there appear to have been no red flags that would have prevented the 18-year-old from obtaining the three guns said to be found in his possession -- the one used in the attack and two guns in his car. He had been evaluated for mental health concerns last year, officials said, but those didn't rise to the level of legal concern.
"Where were the red flags for him to be able to purchase these guns legally?" Erie County, New York, Sheriff John Garcia said. "But in a case like this the gun dealer was able to sell these weapons to this individual because there was no red flags that came up."
Payton Gendron, in the lengthy document posted online, wrote that he bought the AR-15 style gun from a gun store in New York. Gendron had been taken to an emergency room for a mental health evaluation after an incident in high school where he mentioned "murder-suicide," but was released without being involuntarily committed, according to law enforcement officials.
Involuntary commitment could have, if the system worked as designed, resulted in Gendron's name being added to a list of people prohibited from purchasing guns.
Gendron's attorney declined to comment. Gendron is due in court Thursday morning.
New York Gov. Kathy Hochul said the gun used was purchased legally in New York State.
Speaking to CNN's Dana Bash on "State of the Union" on Sunday, Hochul said the weapon was an AR-15. She said it's believed the high-capacity magazine was purchased outside of New York. It's not clear from Hochul's statement describing the weapon as an AR-15 that it is the same item as listed in Gendron's document; police haven't released details yet about the weapon or weapons that were used.
"The gun was purchased in a gun store in New York State legally, an AR-15. But what has made this so lethal, and so devastating for this community, was the high-capacity magazine that would have had to have been purchased elsewhere, that's not legal in the State of New York," Hochul said.
Gendron wrote about buying and modifying an AR-15 style weapon. In New York, magazines can't be larger than 10 rounds, and outside of shooting competitions, can't have more than seven rounds in the rifle at any one time. The AR-style weapon Gendron described wasn't sold with the 30-round magazines common for this type of rifle, when pictured for sale, is almost always pictured with 30-round magazines legal in much of America.
Hochul said it's not clear where the gunman purchased the magazines used in the shooting. Gendron lived right over the state border from Pennsylvania where gun laws are more permissive. Gendron, in his writing, said he bought magazines at a flea market in New York -- which might have been illegal, depending on when he purchased them.
Gendron wrote that the AR-style rifle he bought, because of the lock on the magazine, was legal in New York, but then modified it to remove that lock. At least nine states and the District of Columbia have restrictions, ranging from owning magazines that carry more than 10 or 15 rounds, to banning the sale or purchase of those magazines.
Gendron wrote that he was able to remove the lock with a drill.
Gendron also wrote of two other weapons in the document: a Mossberg 500 shotgun and a Savage Axis XP rifle. At a press conference Monday, Buffalo Police Commissioner Joseph Gramaglia said investigators knew of three weapons -- two located in his car and one Gendron was carrying. Investigators found a rifle and a shotgun in the car; CNN obtained a photo of those weapons. Gramaglia described the gun Gendron allegedly used as an AR-15.
The owner of Pennsylvania Guns and Ammo, a 10-minute drive across the state border from Gendron's hometown of Conklin, New York, told CNN that Gendron legally purchased a shotgun from his store in December 2021. The owner said Gendron claimed he wanted the gun for target practice. He said Gendron was 18 at the time of the purchase and cleared all background checks at his store. He asked not to be identified.
Gendron wrote he acquired the AR-15-style firearm legally and modified it after the fact, an act undetectable to law enforcement or anyone else until the gun is recovered or until someone alerts them to the modification. Robert Donald, the owner of Vintage Firearms, where Gendron wrote he purchased an AR-style rifle, didn't respond to CNN requests for comment.
However, Donald told The New York Times that he sold a Bushmaster rifle to Gendron. Donald told the newspaper he was "shocked" when federal investigators contacted him Saturday to inquire about Gendron.
"I knew nothing about it until I got the call from them. I couldn't believe it," he told the Times. "I just can't believe it. I don't understand why an 18-year-old would even do this," he added. "I know I didn't do anything wrong, but I feel terrible about it."
Donald told the Times he didn't remember Gendron, and added that the background report didn't show anything.
"He didn't stand out — because if he did, I would've never sold him the gun," Donald told the Times.
Garcia, the Erie County sheriff, said the Buffalo shooting suspect was visited last year by New York State Police after he turned in a high school project about murder-suicides.
"The state police arrived at his house at that point last year," Garcia said. "He stayed at a facility, I'm not sure if it was a hospital or a mental health facility, for a day and a half."
Beau Duffy, a spokesperson for the New York State Police, said that "troopers transported the student to the hospital for a mental health evaluation." He confirmed that it was an evaluation and not an involuntary commitment -- so it would not have prevented Gendron from purchasing a gun under federal law.
New York State Police officials also did not seek a "Red Flag" order of protection against Gendron after the incident, which could have been another way to prevent him from purchasing a gun. State police declined to comment on why they didn't seek a red flag order. A law enforcement official told CNN "the threat was general in nature and did not target the school or anyone in particular, and did not specifically mention shooting or firearms."
The state's Red Flag law, also known as the Extreme Risk Protection Order law, was enacted in 2019 and is designed to prevent anyone who shows signs of being a threat to themselves or others from purchasing or possessing a firearm.
According to New York state law, certain clinicians who determine that a patient is "likely to engage in conduct that would result in serious harm to self or others" are required to report that to a county health commissioner, who can report that to the state's Division of Criminal Justice Services, which can block people from buying guns and revoke gun permits.
Federal law prohibits someone involuntarily committed to a mental health institution from buying a gun. It does not cover someone in a mental institution "for observation." A mental institution includes any mental health facility, hospital, or psychiatric ward of a general hospital.
New York has relatively strong laws concerning access to firearms by mentally ill people. Data from the FBI's NICS background check database shows that as of December 2021, there were more than 860,000 people blocked from buying a gun due to adjudicated mental health in New York -- the third-highest total, after California and Pennsylvania.
Social media posts by Gendron claim the investigation into his threat of violence last year ended when he says he told investigators his writings were something he "stupidly" he had done. He was attending Susquehanna High School at the time, in Conklin, last June.
In a post, dated January 30, 2022, Gendron wrote "Another bad experience was when I had to go to a hospital's ER because I said the word's 'murder/suicide' to an online paper in economics class."
"I got out of it because I stuck with the story that I was getting out of class and I just stupidly wrote that down. That is the reason I believe I am still able to purchase guns. It was not a joke, I wrote that down because that's what I was planning to do," according to the post.
Gendron also claims that his mental health evaluation lasted 15 minutes after he spent hours waiting in the emergency room.
CNN has reached out to New York State Police about this account. Investigators have previously said Gendron's threat was of a general nature and not specific enough to warrant further action.
The district attorney in Gendron's hometown said he's reviewing "all aspects" of last year's investigation into the school threat.
"We're even going back several years as far as what his behavior was at that point in time, his relationship with his family, his relationship with teachers and students at the school," Broome County DA Michael Korchak told CNN. "So everything is on the table right now based on this investigation."
Korchak said it's "hard to say" whether more should have been done in June 2021, when the suspect threatened to commit a murder-suicide at his high school.
"The New York State Police were called and they went to the subjects' residence in Conklin and interviewed him and took him to Binghamton General Hospital for a psychiatric evaluation," Korchak said. "So there were no direct threats made to any student or teacher."
According to Korchak, the suspect was 17 at the time. He was treated, released, and cleared to go back to school after that.