(NEW YORK) -- Six months before Nikolas Cruz allegedly gunned down former classmates and teachers at Marjory Stoneman Douglas High School in Parkland, Florida, he apparently texted a photo of an assault rifle, among a slew of other weapons, to a student he repeatedly threatened to kill.
In an exclusive interview with ABC News Wednesday night, Enea Sabadini said it was the one time he did not report Cruz to school officials, despite a tirade of threats and insults from him via social media. Sabadini said he didn’t take Cruz’s messages seriously at the time.
"If I was able to go back, I would have gone and reported him to police and told my mother about it," Sabadini told ABC News.
Sabadini, who plays high school rugby, said his first interaction with Cruz occurred in August 2016. Cruz sent him direct messages on Instagram saying to stay away from his ex-girlfriend, whom Sabadini had just started dating.
At that time, Sabadini hadn’t met Cruz in person and didn’t respond to his messages.
"I was confused why, because I hadn’t had any prior problems with this person," he said. "At first, I didn’t answer back at all."
Sabadini said Cruz’s ex-girlfriend told him to ignore the messages, even though they included racial slurs, threats of murder and even of Cruz feeling depressed.
"you know how f------ mad iam (sic) at you," Cruz wrote in one message. "you took my ex i been depressed."
Still, she said Cruz was “misunderstood.” But, according to Sabadini, she added that he had been “violent and abusive” toward her.
Then one morning, a week or two after school started that year, Cruz approached Sabadini at the school to apologize.
"I think he knew where I sat with my friends in the mornings, so as I was walking toward my usual area, he pulled me aside to apologize," Sabadini said. "I accepted his apology and everything was cool."
Just days later, Cruz again sent hostile messages to Sabadini and threatened some of his friends.
Sabadini, who said he was "confused" by Cruz’s hostility, chose not to respond to the messages again. But he and his friends reported the incident to school officials.
It was unclear whether Cruz was ever disciplined for those messages.
Then, one day after school when Sabadini was leaving school with friends, they noticed Cruz was following closely behind. A brief confrontation between Cruz and Sabadini ensued, in which Cruz yelled at Sabadini to stop talking to his ex-girlfriend.
"We almost get into a fight, but I decide it’s not worth it and I walk away," Sabadini said.
Suddenly, Cruz starts running toward Sabadini with pencils in each of his hands, holding them like daggers, “in a stabbing stance,” Sabadini said.
Sabadini took off running and Cruz chased him down the street, Sabadini said. He eventually outran Cruz and reported the incident to school officials, he said.
Another day at school, Cruz started a fight with Sabadini during lunch. The fight was captured on cell phone video and led to the brief suspension of both students.
"I don’t know why he came up behind me and decided to fight me that day," Sabadini told ABC News. "I was tired of all the things he had been doing to me and my friends."
Sabadini said Cruz continued to send him threatening messages for a few weeks afterward and would occasionally give him the middle finger at school during lunch. The harassment finally stopped only when Cruz was expelled in December 2016, but "out of the blue" in the early morning hours of Aug. 17, 2017, the messaging attacks resumed, Sabadini said.
Eventually, the harassment stopped completely -– until the early morning hours of Aug. 17, the following summer.
In screenshots of the series of Instagram direct messages provided to ABC News, Cruz apparently curses at Sabadini, uses a slew of derogatory insults and threatens multiple times to "kill" him.
"You underground hispanic wall jumper ill (sic) will f------ destroy you," Cruz writes to Sabadini, who is Italian and African American.
After sending the image of guns laid out on his bed, Cruz writes: "Don’t f--- with me!!!!!"
In further direct messages to Sabadini, Cruz says he "stole my ex" and that she meant "everything to me." Cruz writes that he’s been "depressed" and "drinking" ever since, and all he can think about is "hurting" Sabadini.
This time, Sabadini responds to Cruz’s messages, saying he and the girl "broke up" in December 2016. But Cruz continues to threaten him.
"you have no idea what iam (sic) capable of," Cruz writes.
"Iam (sic) going to f-----g kill you."
"Iam (sic) going to watch ypu (sic) bleed.”
Sabadini responds, "F—-- off I’m trying to watch YouTube."
Cruz writes, "I will kill you !!!!!"
"I am going to shoot you dead."
Most of Sabadini’s responses appear nonchalant with a sarcastic tone. He writes, "Hey man you should take a cold shower to calm down, I here (sic) they are refreshing."
Sabadini told ABC News he didn’t take Cruz’s threats seriously at the time. Cruz had been expelled from Marjory Stoneman Douglas High School unspecified disciplinary reasons, authorities said.
"I did not really think much because he was no longer going to our school," Sabadini said. "I just thought nothing of it at the time."
Months later, on Feb. 14, Cruz allegedly opened fire inside the school, killing 17 people and wounding dozens of others, with an AR-15 semi-automatic rifle authorities say he legally purchased a year ago.
When Sabadini heard there was an active shooter on campus, he said he and his friends immediately knew it was Cruz.
"I wasn’t surprised," he told ABC News.
He added that everyone who had interacted with him knew that "if anything was really to happen at the school, like a shooting, that he probably was the only one with enough hate to do so."
Sabadini said he personally knew three of the students who were killed, and that he feels lucky to be alive.
Cruz was arrested and charged with 17 counts of premeditated murder in the aftermath of the attack.
The Instagram account associated with Cruz that directly messaged Sabadini appears to have been taken down.
Sabadini’s mother, Mayi Sabadini, told ABC News she believes it’s important for her son to share his story.
"Even though Nikolas wanted to kill my son, I believe he’s the 18th victim. His life is over, too. He is obviously very, very troubled," she told ABC News in a separate interview.
Mayi Sabadini became emotional when talking about the loss and suffering of so many families, and said she can’t believe her son was sucked in by Cruz's obsession and rage over the ex-girlfriend.
"Kids have to tell their parents about any threat, every single threat. We know that now," she said. "There are many other troubled, sick kids like Nikolas at other schools. I feel very lucky my son is alive."
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