The videos are grim warnings of what was to come. In three recordings released Wednesday, the 19-year-old charged with killing 17 people at a high school in Parkland, Fla., declared with chilling certainty what would happen. He announced plans to become a school shooter, detailed how many people he hoped to murder and gloated about the infamy he would gain from such a massacre.

“When you see me on the news, you’ll all know who I am,” he says before laughing. “You’re all going to die!”

The brief footage offers a macabre glimpse of Nikolas Cruz, who was arrested not long after the Feb. 14 shooting and could face the death penalty. One of the videos appeared to have been filmed the day of the rampage at Marjory Stoneman Douglas High School.

Authorities have not explained why they believe the teenager carried out the shooting. His guilt has not been questioned. Police said he confessed, and his attorneys readily admit he was the gunman. Yet even as it emerged after the massacre that he was a troubled young man with a pattern of disturbing behavior and alleged violence, what motivated him to open fire remains unanswered.

Local and federal authorities were warned repeatedly about his potential for violence, including specific notices to both the FBI and local police that he could open fire in a school. But the warnings all seemingly went unheeded, and authorities say the teenager was able to march into his former school on Valentine’s Day and kill 17 students and staff, wounding 17 others.

Prosecutors have said that he carried out the killings “in a cold, calculated, and premeditated manner.” The videos suggest he had thought about what he would do, and the brief glimpses of what he said drove him carried unnerving echoes of previous mass killers.

Experts who research mass shootings have identified similar characteristics recurring among shooters, including a sense of persecution, flashes of anger and a desire for notoriety through such violence. Some have complained about their lives, while others have described how many people they hope to kill. All of these traits are on display in the brief clips released Wednesday.

The first video begins with the teen, wearing headphones and a baseball cap, looking into the phone’s camera and introducing himself.

“My name’s Nik,” he says. “And I’m going to be the next school shooter of 2018.”

He goes on to say his “goal is at least 20 people, with an AR-15 and a couple tracer rounds,” before identifying his target as Stoneman Douglas, a school in an idyllic South Florida suburb. After announcing that people would die, he then makes cartoonish noises of a gun firing: “Pew pew pew pew! Can’t wait.”

In another video, he says: “Today is the day. Today it all begins. The day of my massacre shall begin.” During a third video, with the camera pointed away, he complains about how his life is “meaningless” and isolated and said he is angry at being called stupid.

“I hate everyone and everything,” he is heard saying. “But the power of my AR you will all know who I am. I had enough of being told what to do and when to do.”

He also shared a message with a female person who is not fully identified, saying: “I hope to see you in the afterlife.”

In his boasts about becoming famous, the teen touched on something that has worried survivors of shootings and their relatives alike. Some have called for news organizations to limit their coverage of mass killers to take away the very infamy those attackers describe as a draw. Survivors of the Parkland attack made a similar argument Wednesday, pleading for attention to be paid to the victims rather than their attacker.

Prosecutors in Broward County, Fla., have said they will seek a death sentence in the case. Representatives for Michael J. Satz, the Broward state attorney, did not respond to requests for further comment about the videos Wednesday.

Howard Finkelstein, the Broward public defender, has said it would be wrong for the state to execute the teen after so many red flags were missed. He has offered to have his client plead guilty and avoid a trial if prosecutors agree not to pursue a death sentence.

Finkelstein said in a statement after the videos were released Wednesday that his team limited its discovery request in the case “so that videos like this and worse would not go public and further hurt and inflame the victims families and the community.” He added: “We continue to stand ready to plead guilty to 34 consecutive life sentences without parole.”

Further reading:

The lives lost in Parkland

Inside an accused school shooter’s mind: A plot to kill ‘50 or 60. If I get lucky maybe 150.’

‘Can you play dead?’ New details about the chaos and fear that surrounded the Parkland massacre.

Broward deputy didn’t go inside Parkland school during shooting because he thought the gunfire was outside, lawyer says

The FBI said it failed to act on a tip about the suspected Florida school shooter’s potential for violence

This story has been updated since it was first published.