More details have emerged of how unstable Florida gunman Nikolas Cruz had become years before he slaughtered 17 people at his former high school.
Cruz, 19, ranted his racist, homophobic and anti-Semitic views in a private Instagram group chat and displayed an obsession with violence and guns.
Cruz wrote that he hated, "jews, ni**ers, immigrants", CNN reports.
He talked about killing Mexicans, keeping black people in chains and cutting their necks, reports News.com.au.
One member of the group joked about Cruz's views, saying that although he hated black people, too, he didn't "to a point I wanna kill the (sic) like nick."
Cruz told the group he hated black people because of their colour. He hated Jews because he believed they wanted to destroy the world.
After one member made their homophobic views known, Cruz said: "Shoot them in the back of head."
Cruz also hated white women and those in interracial relationships, who he saw as traitors.
KILLER'S GUN PASSION BACKED BY NRA
The troubled teen also excelled in an air-rifle marksmanship program supported by a grant from the National Rifle Association Foundation, part of a multimillion-dollar effort by the gun group to support youth shooting clubs and other programs.
Former JROTC cadets told The Associated Press that Cruz was a member of the small varsity marksmanship team that trained together after class and travelled to other area schools to compete.
It was a close-knit group. One of the other cadets started calling Cruz "Wolf," and the nickname stuck.
"He was a very good shot," said Aaron Diener, 20, who gave Cruz a ride to shooting competitions when they were part of the same four-member team in 2016.
"He had an AR-15 he talked about, and pistols he had shot. ... He would tell us, 'Oh, it was so fun to shoot this rifle' or 'It was so fun to shoot that.' It seemed almost therapeutic to him, the way he spoke about it."
The JROTC marksmanship program used air rifles special-made for target shooting, typically on indoor ranges at targets the size of a coin.
Records show that the Stoneman Douglas JROTC program received $US10,827 (NZD $14,652) in non-cash assistance from the NRA's fundraising and charitable arm in 2016, when Cruz was on the squad. The school's program publicly thanked the NRA Foundation on its Twitter feed.
A spokeswoman for the NRA declined to comment on Friday. The top officers of the foundation are all current or former executives of the NRA.
Kyle Ramos, who was the executive officer of the JROTC battalion, said Cruz spoke about guns and knives incessantly and liked to wear military-style clothing to school. He also bragged about shooting animals for fun. "He told me he would attack little animals with pellet guns and stuff, and I was a little weirder out by that," said Ramos, now 20. "Like squirrels and lizards and stuff."
Diener said Cruz sometimes missed target practice because he had detention. There was another time he remembers that Aaron Feis, a member of the school's security staff, came to get Cruz out of JROTC class because he was in some sort of trouble. Feis, who was also an assistant football coach at the school, is among those Cruz is charged with killing.
SHOOTER'S SNAPCHAT VIDEO
Cruz had also cut his arms on Snapchat and said he wanted to buy a gun in September 2016, more than a year before he carried out his own massacre at Marjory Stoneman Douglas High School.
Police and adult welfare investigators from the Department of Children & Family Services investigated the incident four days after he turned 18 and was legally able to buy a gun, the Sun Sentinel reports.
Broward County Sheriff's deputies were called after his late mother Lynda told them he was "cutting his arms ... to get attention," after they had an argument about him getting a Florida State identification card so he could get a gun.
"Mr. Cruz has fresh cuts on both his arms. Mr Cruz stated he plans to go out and buy a gun. It is unknown what he is buying the gun for," the DCFS report stated.
Investigators concluded there were "some implications" for Cruz's safety but determined he was getting adequate support from his school and outpatient care from Henderson Mental Health in Broward County.
Cruz's therapist from Henderson Mental Health, Jared Bienenfeld, was also "on the scene at the home and deemed Nikolas to be no threat to anyone or himself at this present time."
Five months later, he bought an AR-15 rifle — which was used to kill his victims.
Cruz came under DCFS's watch because he was classified as a vulnerable adult due to mental illness.
"[Cruz's] final level of risk is low as [he] resides with his mother, attends school and receives counselling through Henderson," one DCFS investigator wrote.
SHOOTER'S MUM CALLED COPS 30-PLUS TIMES
But the concerns about his welfare had begun years ago, when Lynda had repeatedly called police after his violent episodes at home, where he threatened her and showed self-destructive behaviour, according to police documents obtained by CNN.
Incident reports from September 2016 also stated Cruz was "emotionally handicapped," and taking behavioural medication.
"He has mentioned in the past that he would like to purchase a firearm," one report stated.
Police had been contacted more than 30 times going back to 2011.
Police records detail fights at his private home which were described as "mentally ill person," "child/elderly abuse," "domestic disturbance" and "missing person."
Two calls reported Cruz as missing, in 2012 and 2013.
In November 2012, Cruz's mother Lynda called police after he had hit her with the plastic vacuum cleaner hose.
Lynda was caring for him after she and her husband Roger Cruz adopted Nikolas and his biological younger brother, Zachary after the couple moved from Long Island to Broward County, Florida.
Roger died in 2004 of a heart attack, leaving Lynda to care for the boys. She died from pneumonia in November last year, and they both moved in with a family friend in Palm Beach County.
Many of the calls to police that Lynda made were described as "no paperwork filed," according to a list obtained by CNN.
On January 15, 2013, records show Lynda also called police after Nikolas, 14, "retaliated and threw a chair, dog bowl and a drinking glass across the room" after he refused to go to school. Lynda had removed his Xbox "privileges" and put it in her car.
Nikolas called her a "a useless b*tch".
She told police her son had a "history of developmental and learning disabilities," was "increasingly irate" and had ADHD.
After Nina Barela, a counsellor from the Henderson Behavioral Health facility where Cruz was a client, gave his medication, he began to calm down.
The police reports appear to echo the sentiment his former classmates and neighbours have shared with US media outlets in the wake of the shooting.
Brody Speno knew Cruz since elementary school. He described him as "an evil kid" who was "always getting in trouble."
Longtime Cruz family neighbours Malcolm and Christine Roxburgh told the Sun Sentinel that the police came to the boy's house many times.
Malcolm said a neighbour across the street kept pigs, and Cruz targeted the family.
The FBI made a stunning admission earlier today, saying a "person close to Nikolas Cruz" made a call to the agency's public tip line on January 5 to "report concerns about him." "The caller provided information about Cruz's gun ownership, desire to kill people, erratic behaviour, and disturbing social media posts, as well as the potential of him conducting a school shooting," the FBI said in a statement.
The information from the caller "should have been assessed as a potential threat to life" and forwarded to the agency's Miami field office, it said.
Instead, "no further investigation was conducted." "We have spoken with victims and families, and deeply regret the additional pain this causes all those affected by this horrific tragedy," said Federal Bureau of Investigation director Christopher Wray, who took up his post in August.
Wray said he was "committed to getting to the bottom of what happened," and Attorney-General Jeff Sessions ordered an immediate review to ensure "effective response to indications of potential violence." But Scott, the state governor, nevertheless called for the FBI chief to step down, saying the failure to act was "unacceptable." "Seventeen innocent people are dead and acknowledging a mistake isn't going to cut it," Scott said.
The January warning to the FBI was not the first it had received about Cruz, who used an AR-15-style semi-automatic rifle that he legally purchased a year ago to spray classrooms with bullets.
In September, the FBI was alerted to a message posted on YouTube, in which a user named Nikolas Cruz vowed: "I'm going to be a professional school shooter." The FBI said it had looked into it at the time but was unable to identify the person who made the post.
Cruz was also known to local police after his mother "repeatedly called police to the home to help deal with his violent outbursts, threats and self-destructive behaviour," over the course of several years, according to CNN.
The police incident reports are as recent as September 2016 and one noted "He has mentioned in the past that he would like to purchase a firearm," the network said.
WHERE TO GET HELP:
If you are worried about your or someone else's mental health, the best place to get help is your GP or local mental health provider. However, if you or someone else is in danger or endangering others, call 111.
If you need to talk to someone, the following free helplines operate 24/7:
DEPRESSION HELPLINE: 0800 111 757
LIFELINE: 0800 543 354
NEED TO TALK? Call or text 1737
SAMARITANS: 0800 726 666
YOUTHLINE: 0800 376 633 or text 234
There are lots of places to get support. For others, click here.