As investigators started to question Sayfullo Habibullaevic Saipov, who is recovering in hospital after being shot by a police officer, officials were seeking for clues to how the man who moved to the US in 2010 became radicalised.

Officials said after he left the truck after allegedly mowing down people on a city bike path, Mr Saipov had yelled “Allahu akbar”. Meanwhile, various reports said he left a note in the vehicle claiming he committed the attack for Isis.

New York Truck attack Show all 6 1 /6 New York Truck attack New York Truck attack Investigators inspect the truck following the attack Investigators inspect a truck following a shooting incident in New York on 31 October 2017. Several people were killed and numerous others injured in New York on Tuesday when a suspect plowed a vehicle into a bike and pedestrian path in Lower Manhattan, and struck another vehicle on Halloween, police said. A suspect exited the vehicle holding up fake guns, before being shot by police and taken into custody, officers said. The motive was not immediately apparent. Getty New York Truck attack A paramedic looks at a body along the bike path A paramedic looks at a body covered under a white sheet along the bike path 31 October 2017, in New York. A motorist drove onto a busy bicycle path near the World Trade Center memorial and struck several people Tuesday, police and witnesses said. AP Photo/Bebeto Matthews New York Truck attack The truck driver collided with a school bus Authorities respond near a damaged school bus Tuesday, 31 October 2017, in New York. A motorist drove onto a busy bicycle path near the World Trade Center memorial and struck several people, police and witnesses said. Two adults and two children were on the bus at the time. AP Photo/Bebeto Matthews New York Truck attack A young girl reacts to the scene A young girl reacts as police officers secure an area following a shooting incident in New York on 31 October 2017. Several people were killed and numerous others injured in New York on Tuesday after a vehicle plowed into a pedestrian and bike path in Lower Manhattan, police said. 'The vehicle struck multiple people on the path,' police tweeted. 'The vehicle continued south striking another vehicle. The suspect exited the vehicle displaying imitation firearms & was shot by NYPD.' DON EMMERT/AFP/Getty Images New York Truck attack Police officers arrive at the scene Police officers arrive at the scene following a shooting incident in New York on 31 October 2017. Multiple people were hurt in downtown Manhattan, US media reported after police confirmed that they were responding to reports of a shooting. Police said they had mobilized to the scene in Lower Manhattan and that one person was in custody, giving no further details. DON EMMERT/AFP/Getty Images New York Truck attack Emergency personnel respond to truck attack in lower Manhattan Emergency personal respond after reports of multiple people hit by a truck after it plowed through a bike path in lower Manhattan on 31 October 2017 in New York City. According to reports up to six people may have been killed. Kena Betancur/Getty Images

Officials said Mr Saipov was an Uber and commercial truck driver and had most recently been living in Paterson, New Jersey. Intelligence officials believe the man who was married with two children, was a “lone actor” and was not part of a broader plot.

At the same time, attention has focussed on how and why the young man became radicalised. In the New Jersey neighbourhood he lived in, people said the family had lived in a property on and off for the last three years. Some people said they only saw Mr Saipov attend the local mosque occasionally.

CNN said Mr Saipov has been linked to social media accounts that contain Isis-related material, according to a law enforcement official. The official also said Mr Saipov has been somewhat cooperative with FBI and New York police investigators who questioned him in the hospital overnight.

Footage shows New York terror suspect running through the streets following attack

In an interview with the network the morning after the attack on Lower Manhattan, New York Governor Andrew Cuomo said the suspect was “radicalised domestically”.

He said investigators were still investigating the circumstances leading up to and surrounding the attack. Mr Cuomo said the suspect was a “depraved coward”.

“All the evidence points to a “lone wolf mode”. There is an evolution of tactics for the jihads,” he said. “It’s no longer about training camps in a geographic area. They have a global platform in the internet. And their template is very simple - rent a car, rent a truck, and cause mayhem.”

He added: “He was a depraved coward. He was associated with Isis and radicalised domestically.”