Ahmad Khan Rahami: New York bomb suspect's father warned police he was a terrorist in 2014

Notebook reveals Rahami was influenced by the ideas of Anwar al-Awlaki, al-Qaeda's best known propagandist

Ahmad Khan Rahami is taken into custody after a shootout with police on Monday (AP)

The father of the New York bomb suspect Ahmad Khan Rahami warned that his son was risk two years ago.

On Tuesday morning, after his son had been arrested after a shootout a day earlier, Mohammad Rahami, told reporters gathered outside his home in Elizabeth, New Jersey: “Two years ago I go to the FBI because my son was doing really bad, O.K.?

“But they check almost two months, they say, ‘He’s OK, he’s clean, he’s not a terrorist.’ I say OK”

He added: “Now they say he is a terrorist. I say OK”

His account was confirmed by officials who spoke to The New York Times.

They said his father made the statement about his son being a terrorist to New Jersey police in 2014. It happened when Rahami was arrested after stabbing his brother.

The details were passed to the Joint Terrorism Task Force, led by the Federal Bureau of Investigation in Newark, but the investigation ended when the father withdrew his statement.

Investigators concluded the allegations were made in a fit of anger, but the episode will raise fresh questions about why the young man was not under surveillance.

Rahami, 28, was arrested on Monday after a shootout with police officers in Linden, New Jersey, two days after 29 people were wounded when a bomb exploded in the Chelsea neighbourhood of Manhattan.

Detectives said DNA, fingerprints and CCTV footage all led them to name Rahami as a suspect in an emergency alert sent to millions of people in New York on Monday.

Source: Graphiq

It also emerged on Tuesday that officers found a notebook, pierced with a bullet hole and doused in blood, setting out Rahamis radical views.

The notes praised Anwar al-Awlaki, al-Qaeda's best known propagandist, and the soldier who carried out the Fort Hood shooting, who killed 13 people in 2009.

In one section of the book, Rahami described of “killing the kuffar,” or unbelievers, according to an official who spoke to The New York Times.

They also suspect he was linked to an explosion in a rubbish bin on the New Jersey shore on Saturday.

Investigators are probing Rahami's recent trips to Afghanistan and Quetta in Pakistan.

Officials say he underwent secondary screening on his return to the US each time but passed on every occasion.

On Tuesday it emerged that his wife, who was from Pakistan left the country just a few days before the bombings.

William Sweeney, the FBI's assistant director in New York, said that the FBI was aware of reports about a domestic incident involving Rahami some years ago, but the allegations had been recanted, and "there's nothing to indicate that currently he was on our radar."

Meanwhile, two New Jersey officers wounded in the shootout have been discharged from hospital.

Linden police say Officer Angel Padilla went home on Monday night, several hours after he was shot in the torso. Authorities have said a bulletproof vest saved him from a more serious injury.

Another Linden officer, Pete Hammer, was released a day late. Authorities said his head was grazed by a bullet.