A woman is aided by first responders after sustaining injury on a bike path in lower Manhattan in New York, NY, US, October 31, 2017. [Photo/Agencies]

On Twitter, US President Donald Trump called it "another attack by a very sick and deranged person" and declared, "NOT IN THE USA.!" While police did not specifically blame the Islamic State for the New York bloodshed, Trump railed against the extremist group, tweeting, "We must not allow ISIS to return, or enter, our country after defeating them in the Middle East and elsewhere. Enough!"

Police said Saipov rented the truck at about 2 pm in New Jersey, entering the bike path about an hour later on West Street a few blocks from the new World Trade Center, the site of the deadliest terror attack in US history. The truck then turned at Chambers Street, hitting the school bus and injuring two adults and two children.

A paintball gun and a pellet gun were found at the scene, police said. At least two covered-over bodies could be seen lying on the bike path, and the front end of the truck was smashed in, as was the side of the school bus.

Tom Gay, a school photographer, heard people saying there was an accident and went down to West Street, where a woman came around the corner shouting, "He has a gun! He has a gun!" Gay said he stuck his head around the corner and saw a slender man in a blue tracksuit running on West Street holding a gun. He said a heavyset man was chasing him.

He said he heard five or six shots, and the man in the tracksuit fell to the ground, gun still raised in the air. He said a man came over and kicked the gun out of his hand.

AP