There were glaring warning signs in the years before Nikolas Cruz gunned down 17 people at Marjory Stoneman Douglas High School in Florida— including an obsession with guns, blood and murder, according to trial testimony.

Cross Creek School health officials, Dr. Nyrma Ortiz and therapist Rona O’Connor, wrote a 2014 letter to Cruz’s psychiatrist, Dr. Brett Negin.

"He is usually very irritable and reactive," they wrote of the then-15-year-old student who was enrolled in the special needs school.  "He dreams of killing others."

They also described Cruz as obsessed with guns, belligerent and paranoid. 

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Nikolas Cruz in court Aug. 22, 2022, in Florida

Nikolas Cruz, 23, in court Monday, Aug. 22, 2022, at his penalty trial.  (Amy Beth Bennett/South Florida Sun Sentinel via AP, Pool)

"At home, he continues to be aggressive and destructive with minimal provocation," the pair wrote. 

After losing a video game, he took his rage out on a television set. On another occasion, he took out his frustration by punching holes in a wall and using sharp objects to slice up the family’s furniture. 

The two health professionals said they were writing to request that Negrin adjust his medication.

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But Negrin testified Wednesday that he never received the letter, and no one from the school followed up after he didn't respond.

A year prior, Negin wrote a letter for Cruz’s mother supporting his voluntary hospitalization — but the child was never admitted.

Dr. Brett Negin testifying Aug. 25, 2022

Psychiatrist Dr. Brett Negin testifies during the penalty trial of Marjory Stoneman Douglas High School shooter Nikolas Cruz Aug. 25, 2022. (Amy Beth Bennett/South Florida Sun Sentinel via AP, Pool)

The troubled teen was taking medications for attention deficit hyperactivity disorder and other disorders— but Negin said he never observed behavior that suggested Cruz was capable of mass murder.

It was the fourth day of the defense’s case in Cruz’s penalty trial. Cruz, 23, pleaded guilty to 17 counts of first-degree murder in October. The trial in Broward County Circuit Court, in Fort Lauderdale, will determine only whether Cruz is sentenced to death or life in prison without parole.

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The defense has argued that Cruz was born damaged after his biological mother, a sex worker, abused alcohol and crack while she was pregnant with him. 

He was adopted as an infant — but his mother, Lynda Cruz, had difficulty coping with his behavioral and emotional deficits, which were never properly treated, according to his lawyers.

mugshots of Nikolas Cruz's birth mother and half-sister

Nikolas Cruz’s biological mother Brenda Woodard (left) and his half-sister Danielle Woodard have lengthy criminal histories. (Florida Department of Corrections via AP/Florida Department of Corrections)

More than four years ago, Cruz used an AR-15-style semiautomatic rifle to spray hallways and classrooms with bullets — killing 14 students and three staffers.

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For seven minutes, he stalked the three-story building, taking a second pass at some students who were injured and killing them, according to trial testimony. 

The verdict must be unanimous. If a single juror votes against the death penalty, Cruz will be sentenced to life in prison.