THE man accused of ploughing into people on a lower Manhattan bike path on Tuesday had apparently been planning the attack for a number of weeks, officials said.
"He did this in the name of ISIS, and along with the other items recovered at the scene was some notes that further indicate that," John Miller, deputy commissioner of Intelligence and Counterterrorism of the NYPD, said on the attack that killed eight.
"He appears to have followed almost exactly to a 'T' the instructions that ISIS has put out in its social media channels before with instructions to their followers on how to carry out such an attack."
The sole suspect, identified as 29-year-old Sayfullo Saipov, reportedly left a note in his rental truck that read "ISIS Lives Forever".
Eight people were killed and 12 seriously injured in the Tuesday afternoon attack when, authorities say, Saipov barrelled along the path in a pick-up truck for more than a dozen blocks.
He was shot in the abdomen by a police officer and was transported to a hospital for treatment.
Police said Saipov was first interviewed by the FBI in 2015 - but officials didn't have enough information on him to open a case, according to a new report.
Authorities with the Department of Homeland Security Investigations Unit had probed Saipov about his possible ties to suspected terrorists, ABC News reported.
Saipov's name and address were listed as a "point of contact" for two men whose names were on the Counterterrorism and Criminal Exploitation Unit's list after they arrived in the US from "threat countries," a federal source told ABC.
Saipov has reportedly been interviewed by police in hospital. He allegedly showed no remorse for the lives he had taken with a source telling ABC News in the US that he seemed "proud" and the New York Post said he was "boasting".
TRUMP CALLS FOR END TO DIVERSITY VISA PROGRAM
US President Donald Trump called Saipov an "animal" and has said he will ask Congress to close the immigration lottery program.
Mr Trump said on Twitter that the driver in Tuesday's attack "came into our country through what is called the 'Diversity Visa Lottery Program,' a Chuck Schumer beauty."
Officials said the attacker is an immigrant from Uzbekistan who came to the US legally in 2010. They haven't said whether he came in through the Diversity Immigrant Visa Program, which covers immigrants from countries with low rates of immigration to the US.
Mr Trump tweeted, "We are fighting hard for Merit Based immigration, no more Democrat Lottery Systems. We must get MUCH tougher (and smarter)."
Mr Trump also said he would "certainly consider" sending the New York suspect to Guantanamo prison.
FRIEND OF SAIPOV SAYS HE HAD RADICAL VIEWS
As counter-terrorism investigators drilled into whether Saipov had had meaningful ties to terrorist organisations, it also became clear that some of those close to the attacker had feared for years that he was heading down the path of extremism.
An Ohio truck driver says Saipov was argumentative and seemed to harbour radical views and saw his work life spiralling down.
Mirrakhmat Muminov says Saipov lived in Stow, Ohio, for a few years. He says he knew Saipov because they were both Uzbek truck drivers.
Muminov says Saipov lost his insurance on his truck because of a few traffic tickets. He says companies stopped hiring Saipov, so he left for New Jersey.
Muminov said he heard from Saipov's friends that Saipov's truck engine blew up a few months ago in New Jersey. He says that "probably hurt him more than anything."
Muminov also says Saipov was "not happy with his life" and would get into arguments with his friends and family.
Muminov says Saipov never spoke about Islamic State, but he could tell Saipov held more radical views.
POLICE OFFICER PRAISED FOR STOPPING ATTACKER
Police officer Ryan Nash was out on a routine call - to locate an emotionally disturbed person - when suddenly, he came face-to-face with a terrorist committing the worst massacre in New York City in years.
Nash, 28, who is stationed in the First Precinct, stopped the killing spree by shooting Sayfullo Saipov near Stuyvesant High School at Chamber and West streets on Tuesday, police sources said, reports the New York Post.
Saipov shouted "Allahu akbar!" - Arabic for "God is great!" - after allegedly ramming a Home Depot rental pick-up truck into people along a bike path, killing eight. He then whipped out two weapons - which turned out to be a paintball gun and pellet gun - as he ran from his smashed truck.
Mr Nash gave chase, drew his weapon and opened fire, bringing down the 29-year-old suspect before he could do any more harm, law-enforcement sources said.
Mr Nash, who lives in Medford, Long Island, was taken to Bellevue Hospital, where he was treated for ringing in his ears.
The fast-acting cop has been on the job for more than five years with more than 50 arrests to his credit, sources said.
"A uniformed police officer ... confronted the subject and shot him in the abdomen," NYPD Commissioner James O'Neill said.
ONE VICTIM'S PARENTS SPEAK OUT
One of the victim's of Tuesday's terror attack is a 32-year-old New Jersey man who was biking between meetings in an effort to lose weight, his devastated parents told the New York Post.
Darren Drake, a project manager at Moody's, had bought a CitiBike membership in an effort to get fit, said mum Barbra.
"He was riding his bike in between meetings - I guess he was in the wrong place at the wrong time," Barbra Drake, 69, said after returning from the coroner's office.
"He was trying to lose weight, trying to stay active. So he signed up for that Citibike group … he was trying to do everything right. Trying to take care of himself."
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