The attacker, Artyom Igorevich Kazantsev, was identified by Russia's Investigative Committee. He was 34 years old and had a documented history of mental illness. In 2007, while serving in the military in the Chelyabinsk region, he had attempted suicide by cutting his wrists. Years before the school attack, he had stabbed two passersby and been referred for psychiatric evaluation. A magistrate at the Oktyabrsky District Court of Izhevsk reviewed the psychiatric findings but chose not to impose compulsory treatment — a decision that would later come under intense scrutiny. Investigators found that Kazantsev harbored neo-Nazi and neo-fascist views. He carried keychains honoring the perpetrators of the 1999 Columbine High School massacre in the United States. He had purchased empty pistol magazines legally from specialized stores on four occasions; investigators believe he acquired ammunition illegally or through forged documents.

Twenty minutes before the attack, Kazantsev sent an email. He had also left a file on his computer titled "Manifesto" after deleting everything else. In it, he wrote that he had originally planned to kill his mother but changed his mind, fearing it would derail what he called his larger plan. The document expressed hatred toward government institutions, specific political and cultural figures, and contained his assessment of current events. Law enforcement authorities were forbidden from making the manifesto public. Kazantsev had studied the tactical responses to previous school attacks in Russia, analyzing how operational services had stormed buildings to neutralize shooters. He entered School No. 88 prepared for what he intended to do. The attack claimed the lives of three teachers, two security guards, a cloakroom attendant, and a cleaner, in addition to the eleven children.

Among the survivors, the injuries were devastating. Eleven children were left permanently disabled. One of them, ninth-grader Robert Burkhanov, was shot in room 403. The bullet entered his head and exited through his temple, leaving him paralyzed. Two years after the attack, as of September 2024, he had still not regained consciousness. His mother remained at his side. Doctors said there was no chance of recovery. By September 2025, his eyes had opened, but he remained unconscious and in palliative care. His case became a symbol of the attack's ongoing toll — a reminder that for the families of the wounded, September 26, 2022, never ended.

The shooter killed himself during the attack. Spontaneous memorials appeared in cities across Russia and abroad. Russian President Vladimir Putin and Prime Minister Mikhail Mishustin issued statements. International condolences came from Chinese President Xi Jinping, the United Nations, the European Union, the Egyptian Ministry of Foreign Affairs, and the U.S. Embassy in Moscow. The Izhevsk shooting joined a grim list of school attacks in Russia that includes the 2004 Beslan hostage crisis, the 2018 Kerch Polytechnic College massacre, and the 2021 Kazan school shooting. Investigations afterward focused on how Kazantsev had been able to acquire weapons despite his psychiatric history and prior violent acts, and on the court decision that had declined to mandate his treatment years earlier. A memorial park was established in Izhevsk to honor the victims.