A MAJOR manhunt is underway after a shooter opened fire on at least three people in The Bronx following a terrorist attack in Manhattan.
The suspect is still on the run following the incident, which took place on Randall Avenue north-east of Manhattan.
PIX11: At least three people shot in the Bronx on Randall Avenue—conditions of the victims unknown pic.twitter.com/prXxDhF6ZC— Josh Caplan (@joshdcaplan) November 1, 2017
One person is believed to have been shot in the head and another is in critical condition, sources reportedly told New York's Pix 11. The other two victims are reportedly in a stable condition.
It comes just hours after at least eight people were killed in a vehicle ramming attack. Sayfullo Saipov, 29, drove the wrong way at high speed down a bike path in Battery Park City near the World Trade Centre site at 3.15pm local time (5.15am AEDT).
He rented a utility vehicle from Home Depot an hour earlier before smashing it into a school bus outside Stuyvesant High School.
Meanwhile, on the other side of New York, are starting to emerge about the "very sick and deranged person" police believe killed at least eight people in a New York truck attack.
Sayfullo Saipov, 29, had notes written in Arabic inside his rented ute along with either an Islamic State flag or a smaller picture of a flag, law enforcement sources told The New York Post.
The handwritten notes indicated that he had pledged allegiance to the terror group, the sources said.
Saipov was shot and taken into custody by police, after he injured at least 15 people near the site of the World Trade Centre attacks, at 3.15pm Tuesday afternoon local time.
Saipov emerged from the ute with fake guns in both hands and ran toward a crowd of children before he was gunned down by police.
He was heard to scream "Allahu Akhbar" as he leapt out of the ute.
Saipov reportedly arrived in the US from Uzbekistan in 2010, and had a green card that allowed him to live there permanently.
A shocked friend told the Post he was normally "very friendly" and had worked as an Uber driver. He was unware he had any links to terrorism or had been radicalised.
Kobiljon Matkarov, 37, met Saipov in Florida soon after Saipov arrived in the country.
"He is very good guy, he is very friendly… he is like little brother… he look at me like big brother," Mr Matkarov said.
He believed his friend had been recently living in New Jersey, which is where the Home Depot ute had been rented from.
"My kids like him too, he is always playing with them. He is playing all the time," Matkarov said.
He last saw him in June when Saipov dropped his family at the airport - the only thing odd about that encounter was when he refused to be photographed.
"He no like that. He said no," Matkarov said.
Two children travelling on a school bus were among the injured, after the truck rammed into the side of the vehicle.
No victims' names have been released, but Argentina's Foreign Ministry confirmed "Argentine citizens died".
US President Donald Trump said it appeared to be the work of "a very sick and deranged person".
New York Mayor Bill de Blasio told a media conference the attack was a "cowardly act of terror aimed at innocent people ... who had no idea what was about to hit them".
Governor Andrew Cuomo called it a "lone wolf" attack. He said there was no evidence to suggest it was part of a wider plot.
Six men were pronounced dead at the scene while two other people were taken to hospital and died there.
"We also transported 11 people, all with serious but at this moment not life-threatening injuries. The injuries are what you might expect when a truck at high speed went down that bicycle path and struck cyclists and pedestrians. There may be more injuries and we will determine that later," New York City Fire Commissioner Daniel Nigro said.
The man hit a school bus that was carrying two adults and two children, before he drove onto the bike path. Dramatic images showed mangled bikes left strewn across the pavement, while two bodies could be seen lying under a tarp.
The attack came just hours before New York's annual Halloween parade, which attracts thousands to the West Village, a few blocks north of Lower Manhattan.
It's believed the people killed were run over by the truck, rather than being shot. Police told local media the guns the motorist was carrying were fake - a paint gun and a pellet gun.
Elizabeth Chernobelsky, 17, a 12th grade student at Stuyvesant High School, said the school went into lockdown for three hours after the attack.
The teenager saw the bomb squad rush in and bodies being taken away from the scene in body bags.
"It was very shocking, like out of the movies," she told news.com.au.
"What sticks in my mind is that it was taking a really long time.
"There were hundreds of police staff members and they were just circling around the bodies."
Student Tawhid Kabir, 20, told news.com.au from near the scene: "I came out and saw a cop. I thought it was an accident so I went to see what happened."
He said he saw a man with "two guns".
"He was running in the middle of the street ... there was another guy not in a cop uniform who was also chasing him."
The students all dropped to the ground when shots, now thought to have been fired by police, rang out. When I heard the gunshots I was so scared."
Local worker Eugene Duffy described to news.com.au the anguished screams he heard as the attack unfolded.
"I heard a woman. It was a different kind of yelling, a different kind of screaming. A very scary scream."
He turned and saw the attacker's ute.
"I immediately think something bad is happening ... I [saw] the truck drive into another car."
He didn't see the man - but saw panicked people running every direction they could to get to safety.
Mr Duffy said it was lucky that it happened on the West Side Highway on a weekday, not on a weekend.
"There's always joggers, people walking their dogs and riding bikes."
A young girl watched the carnage happen.
"I feel very bad for that girl. She must have seen it all," she said.
Simranjeet Kalra, 21, of Long Island, said she saw two dead cyclists who had been riding City Bikes.
"What happened was there was a car crash … he came out of one of the cars. He had two guns. He was running around Chambers and somebody started to chase him," another Stuyvesant student Laith Bahlouli, 14, said.
"I heard four to six gunshots - everybody starts running."
The attack occurred in the shadow of the World Trade Centre and in the middle of an education precinct that was filled with students, leaving those at the scene to question if that had been why the area was targeted.
The man was seen running towards a group of children when he got out of the ute.
Local streets were filled with police and media - but despite horrific the attack kids and parents are still walking past in in steady streams wearing Halloween costumes and big smiles on trick-or-treating missions.
Witnesses described a scene of terror, saying the shooter ran over two people before ploughing into a school bus.
"Jesus! A car just ran over 2 people and then crashed into a school bus. I see two dead bodies and citibikes on the floor destroyed," a Twitter user wrote.
The suspect then got out of his vehicle with two guns, another witness said. Video of the scene shows at least two people lying limp in the street.
Photos show a smashed up Home Depot rental truck, and two mangled Citi Bikes. Counter-terror police were searching the truck for explosives.
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