Credit: Twitter / @ohwelljane, Ruben Roi, Charles Eckert, Tawhid Kabir

This story was reported by Anthony M. DeStefano, Maria Alvarez, Laura Figueroa Hernandez, Matthew Chayes, Stefanie Dazio, Robert E. Kessler, Mark Morales, Michael O’Keeffe, Pervaiz Shallwani, Joan Gralla, Chau Lam and Emily Ngo. It was written by Bart Jones.

Investigators worked overnight to find out what led a lone-wolf terrorist to drive a rented pickup truck Tuesday and careen down a bike path next to the Hudson River, killing eight people, six of them foreign tourists, officials said.

At least 11 other people were injured in the worst terrorist event in New York City since Sept. 11, 2001, when the World Trade Center towers — just blocks away from Tuesday’s attack — came crashing down. Investigators reportedly found a handwritten note in the truck pledging allegiance to ISIS.

The rampage began at 3:05 p.m. Tuesday, when the suspect, identified by sources as Sayfullo Saipov, 29, an Uzbekistan immigrant, drove a rented Home Depot truck, entering the West Side Highway bicycle path at Houston Street, mowing down bikers and pedestrians on the waterfront pathway until he left at Chambers Street.

He collided with a school bus near Stuyvesant High School, injuring two adults and two children inside, and emerged from the vehicle holding what appeared to be two firearms — later recovered and determined to be a paintball gun and a pellet gun — after the crash, officials said.

An NYPD officer assigned to the First Precinct, Ryan Nash, 28, of Medford, stopped the attack when he shot the man in the abdomen. The suspect was taken into custody, and sources said he was taken to Bellevue Hospital Center. The AP reported he was in critical condition but was expected to survive.

NYPD Commissioner James O’Neill praised the officer, saying he “stopped the carnage moments after it began.”

Mayor Bill de Blasio said it was a “very painful day in our city. . . . This was an act of terror. And a particularly cowardly act of terror aimed at innocent civilians, aimed at people going about their lives who had no idea what was about to hit them.”

Sayfullo Saipov, left, is shown in an undated photo provided...

Sayfullo Saipov, left, is shown in an undated photo provided by the St. Charles County Department of Corrections via KMOV. Right, the scene after a truck was driven down a bike path in NYC on Oct. 31, 2017. Credit: KMOV via AP; Charles Eckert

The attack was launched by a suspect whom Gov. Andrew M. Cuomo called the type of “lone wolf” increasingly responsible for such attacks. O’Neill said the suspect made statements that “enabled us to label it a terrorist event.”

Witnesses told police the suspect shouted “Allahu akbar,” which means “God is great,” a law enforcement source said.

Fire Commissioner Daniel Nigro said six people – all males - were pronounced dead at the scene between Houston Street and Chambers Street. Two others were transported in traumatic arrest and were pronounced dead at the hospital.

“We also transported 11 people, all with serious but, at this moment, not life-threatening injuries. The injuries are what you may expect as a truck went at high speed down that bicycle path and struck bicyclists and pedestrians,” Nigro said.

The Argentine Consulate reported that Argentinian citizens were among those killed. The men were: Hernán Mendoza, Diego Angelini, Alejandro Pagnucco, Ariel Erlij and Hernán Ferruchi. The five, and a sixth man who was injured, were part of a group of friends in New York to celebrate the 30th anniversary of their school graduation. The Belgian Consulate reported one of its citizens was killed, the AP reported.

Tawhid Kabir, 20, a student from the Borough of Manhattan Community College, said he ran up a pedestrian bridge on Chambers Street and saw the gunman “chasing a man up West Street with two guns in his hands. When I heard the shots I went down on the ground ”

When Kabir stood up, he saw two bodies lying on the highway. “I saw the police put sheets over them,” he said.

Sources identified the suspect as a native of Uzbekistan from Paterson, New Jersey. He came from Uzbekistan about five or six years ago, moving to Florida and has a green card, the sources said.

The case is being jointly investigated by the FBI and the NYPD, who consider it to be an act of terrorism, but the suspect apparently acted alone, the sources said.

Cuomo, who was in Manhattan, called the suspect one of the “lone wolves who commit an act of terror” using “new terrorist tactics . . . At this point, there’s no evidence suggesting a wider plot or a wider scheme.”

A bomb squad and K-9 units were at a Home Depot in Passaic, New Jersey, Tuesday night, investigating a car parked there related to the suspect, a law enforcement source said.

The Passaic County sheriff’s bomb squad and K-9 units were requested to go to the store, the source said. FBI agents and NYPD officers were also there.

“We are involved in a multi-jurisdictional investigation” at the Home Depot, said Passaic Police Deputy Chief Christopher Storzillo.

Stephen Holmes, a spokesman for Home Depot, would not say where the driver rented the truck. “We’re cooperating with authorities on the investigation,” Holmes said.

The attack came on a clear autumn day just hours before the city’s Halloween festivities began.

“The dead and injured were just going about their days, heading home from work or from school, or enjoying the afternoon sun on bicycles,” said O’Neill. “This is a tragedy of the greatest magnitude for many people, for many families here in New York City and beyond today.”

President Donald Trump, a native New Yorker, tweeted: “In NYC, looks like another attack by a very sick and deranged person. Law enforcement is following this closely. NOT IN THE U.S.A.!”

First lady Melania Trump tweeted: “My heart breaks for #NYC today. Thoughts & prayers as we monitor the situation.”

Tuesday night, the president tweeted again, saying, “I have just ordered Homeland Security to step up our already Extreme Vetting Program. Being politically correct is fine, but not for this!”

A spokesperson for the nation’s oldest Muslim organization, the Ahmadiyya Muslim Community USA, put out a statement saying, “We mourn the lives lost in New York City and stand in solidarity with our fellow Americans.”

Cardinal Timothy Dolan, Archbishop of New York, released a statement saying, “No matter our religion, racial or ethnic background, or political beliefs, we must put our differences aside and come together in faith and love to support those who are injured, pray for those who have died as well as their families and loved ones, and work towards greater respect and understanding among all people so that heinous and evil acts like this become a thing of the past.”

Officials urged New Yorkers to resume their typical activities. The Village Halloween Parade went on but with additional police officers and heavy-weapons teams. The parade runs from Sixth Avenue and Spring Street to 16th Street.

O’Neill also said heavy-weapons teams would be deployed citywide. The New York City Marathon is scheduled for this Sunday, and there was no immediate indication it would be canceled.

“We know this action was intended to break our spirit . . . and our spirit will never be moved by an act of violence,” said de Blasio. “New Yorkers do not give in in the face of such actions.

“We’ll respond as we always do. We will be undeterred,” he added.

Witnesses said they were stunned by the scenes of horror that took place in Lower Manhattan Tuesday afternoon.

“This is not supposed to happen here. This is a fancy neighborhood were the one percent live,” said Raquel Martinez, 30, of Jamaica, Queens, who was on her lunch hour when mayhem broke out.

John Williams, 22, a student at Brooklyn College, said he was walking in the direction of the shooting near the West Side Highway when he heard shouts of “He has gun! He has a gun!”

Williams said he heard a succession of about five gunshots “one after another, it was very fast” when he came upon a white Home Depot truck that had its front windshield smashed and smoke coming out of it.

Williams said he saw “one man lying in the road like he’d been shot” next to the car and NYPD officers arresting a heavyset man next to the man on the ground.

“One thing that was noticeable was the smell of gun powder . . . It filled the air,” Williams said.

A doorman at nearby building on Chambers Street said he saw people gathering and looked outside, where he saw two trucks had collided, and a man in a blue track suit with a red horizontal stripe — and something in his hand — was being chased by another man.

“Right after that, I heard five or six gunshots, boom, boom, boom,” he said. The police arrived and “Apparently, they took the guy down . . . it all happened so fast,” he said.

Sen. Chuck Schumer (D-N.Y.) issued a statement saying: “As one of thousands of New Yorkers who regularly rides on the path where this attack took place, I’m particularly grateful to the NYPD and first responders who work day in and day out to keep us safe, and to those that responded to the scene today.”

Suffolk police released a statement expressing “sincere condolences” and added: “There is currently no increased credible threat to Suffolk County.”

Cuomo, at the news briefing, said the attack “reminds us all how precious life is.” The victims “left the house this morning — they were enjoying the beautiful Westside of Manhattan on a beautiful fall day and they are not going to be returning home. And that shock and that pain is going to be very real.”

“The truth is, New York is an international symbol of freedom and democracy — that’s what we are — and we are proud of it,” Cuomo said. “That also makes us a target for those people who oppose those concepts, and we’ve lived with this before, we’ve felt the pain before, we feel the pain today, but we go forward together and we go forward stronger than ever.”

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