In the wake of the tragic shooting at Perry High School in Iowa on Thursday, authorities have begun investigating the social media posts made by the gunman, 17-year-old Dylan Butler. The incident left one person dead and five others injured.

Butler, a former student at the school, was found dead at the scene. The motive behind the attack is currently under investigation, with particular attention being paid to a number of social media posts made by Butler around the time of the shooting.

Moments before the attack, Butler allegedly posted a chilling video on TikTok with the caption "Now we wait." The video depicted Butler in a bathroom stall at the school, holding a blue duffle bag. The accompanying music was the same as that used on the personal website of Eric Harris, one of the shooters involved in the 1999 Columbine High School massacre.

Investigators also discovered pictures on Butler's social media accounts showing him posing with firearms. Federal and state investigators are currently interviewing Butler's friends and analyzing his online activity, including his posts on TikTok and Reddit.

Law enforcement officials have confirmed that Butler acted alone during the shooting. He was armed with a pump-action shotgun and a small-caliber handgun, with which he killed one sixth-grader and injured five others. Among the injured was Perry High School Principal Dan Marburger.

Although one of the victims remains in critical condition, their injuries are not believed to be life-threatening, according to Mitch Mortvedt, the assistant director of the state investigation division. The other victims are reported to be in stable condition.

Authorities have also revealed that a crude improvised explosive device was found in the school premises, but it was quickly rendered safe.

Following the incident, Iowa Governor Kim Reynolds expressed her condolences and described the shooting as a "senseless tragedy" that has deeply affected the entire state. White House Press Secretary Karine Jean-Pierre also addressed the shooting, describing it as "tragic" and questioning when such acts of violence will end.

As of now, Perry High School remains closed, while investigators continue their efforts to understand the events leading up to the devastating shooting.